| ||||||
*Compared to average sales price on eBay.co.uk during the last 15 days | ||||||
Casio FX-991ES Scientific Calculator
|
Manufacturer Part: FX-991ES
Brand: Casio
Model: FX-991ES
Digit Display: 12 Digit
Power Source: Battery / Solar
Product ID: EPID57341568
Buy this item
Sort by:
Reviews
Casio FX-991ES. A ReviewReview created: 21/02/07(updated 27/02/07)
by:
frankpantzaris ( 1 )
4 of 4 people found this review helpful.
This beautifully made calculator has 403 functions and can do not only numerical integration and regression with two variables, permutations and combinations, but also has a "solve" function for equations and can also solve simultaneous equations and matrices.
The key action is perfect, as we have come to expect from Casio and thank goodness the lettering is black on white and not that awful yellow and red on black (a Casio favourite), which is so difficult to read at home at night. This model is solar powered, supported by a small button battery(much less expensive than lithium). In all other respects it is identical with FX-570ES which is not solar but uses one standard AAA torch battery and sells at the same price. It remains to be seen which model will prove more popular.
But perfect though these two models are for what they do, they have one important deficiency which prevents me from giving them an "excellent" score. They are not programmable, which means they are designed for school and college work rather than for serious scientific or professional work. What a pity!
The key action is perfect, as we have come to expect from Casio and thank goodness the lettering is black on white and not that awful yellow and red on black (a Casio favourite), which is so difficult to read at home at night. This model is solar powered, supported by a small button battery(much less expensive than lithium). In all other respects it is identical with FX-570ES which is not solar but uses one standard AAA torch battery and sells at the same price. It remains to be seen which model will prove more popular.
But perfect though these two models are for what they do, they have one important deficiency which prevents me from giving them an "excellent" score. They are not programmable, which means they are designed for school and college work rather than for serious scientific or professional work. What a pity!
Review ID: 10000000003007247
Was this review helpful? Report this review
Thank you for voting. If your vote meets our 
Casio Calc.Review created: 08/05/08
by:
) 2 of 2 people found this review helpful.
The calculator is excellent, and I got it for only £8.51. I find it easy to use and it handles everything I can throw at it. It is also good for the environment - an important feature to consider when purchasing anything, as it has solar panels.
Review ID: 10000000007065743
Was this review helpful? Report this review
Casio FX-991ES Calculator will save your maths grade2 of 2 people found this review helpful.
I love this calculator, the range of functions is endless and it is so easy to use. It will have truly saved my maths exam marks. If your worried that this is not allowed by exam boards, it is!
Review ID: 10000000003670826
Was this review helpful? Report this review
Casio FX-991ES, Scientific Calculator2 of 2 people found this review helpful.
This model, together with the FX-570ES, are the most advanced scientific calculators in the current Casio range. The two models are identical, except that this one is powered by a solar cell and a small LR44 button battery, while the other requires an ordinary, cheap, AA torch battery, which I think is preferable. At last calculator manufacturers seem to have realised that lithium batteries, at retail prices, eventually cost more than their calculators.
Another great improvement from earlier models is the keyboard base, which is now silver and so far easier to read in any lighting, than the previous Casio favourite, that awful black, which was impossible to read at home at night. The key action is very good, soft with a slight click, as we have come to expect from Casio, but I would still prefer it slightly softer, as in some earlier models, for faster operation. The calculating facilities it offers are excellent: 403 functions, including solve, calc, 3 simultaneous equations, matrices, bivariate regression etc, plus the dubious benefit of 40 constants.
The finish and workmanship are first class.
But excellent though this model is in all the above, it does have some disadvantages compared with previous models, which prevent me from giving it an "excellent" overall rating. The main one is that it has no programmability at all and so it is more suitable for schools and collages, rather than for serious professional or scientific work. -The grafic models are not the answer as they are big and heavy, difficult to learn and much slower to operate-. Another shortcominbg is that it omly has 7 memories, and storing numbers into them is clumsy and slow, requiring 3 key strokes on distant keys, instead of the usual 2. So does fixing the number of decimal points. Its logic with memories is also less efficient than previously. It is a pity that manufacturers so often take 2 steps forward and 1 step backwards. I hope one day Casio will correct these shortcomings and they will then have a world beater. My rating is: "Very good"
Another great improvement from earlier models is the keyboard base, which is now silver and so far easier to read in any lighting, than the previous Casio favourite, that awful black, which was impossible to read at home at night. The key action is very good, soft with a slight click, as we have come to expect from Casio, but I would still prefer it slightly softer, as in some earlier models, for faster operation. The calculating facilities it offers are excellent: 403 functions, including solve, calc, 3 simultaneous equations, matrices, bivariate regression etc, plus the dubious benefit of 40 constants.
The finish and workmanship are first class.
But excellent though this model is in all the above, it does have some disadvantages compared with previous models, which prevent me from giving it an "excellent" overall rating. The main one is that it has no programmability at all and so it is more suitable for schools and collages, rather than for serious professional or scientific work. -The grafic models are not the answer as they are big and heavy, difficult to learn and much slower to operate-. Another shortcominbg is that it omly has 7 memories, and storing numbers into them is clumsy and slow, requiring 3 key strokes on distant keys, instead of the usual 2. So does fixing the number of decimal points. Its logic with memories is also less efficient than previously. It is a pity that manufacturers so often take 2 steps forward and 1 step backwards. I hope one day Casio will correct these shortcomings and they will then have a world beater. My rating is: "Very good"
Review ID: 10000000003272561
Was this review helpful? Report this review
Very good calculator1 of 1 people found this review helpful.
For all people doing A levels make sure you get one this i a very good calculator and no point making the exams harder for yourself
Review ID: 10000000006456223
Was this review helpful? Report this review
A Good CalculatorReview created: 09/03/08
by:
) 1 of 1 people found this review helpful.
This calculator is very easy to undertand and use. It covers all aspects used in my sons school. Great value for money - much better than when I had one for my schooling !! years ago!
Review ID: 10000000006093588
Was this review helpful? Report this review
Scientific And Then Some !!!
) 1 of 1 people found this review helpful.
This was a gift for my husband, he already owns one, but was worried sick incase it got lost or damaged, so now he has a spare, it's the only model he has found that can cope with the complexities of the maths he's doing at the moment. Excellent machine for higher education courses.
Review ID: 10000000005260425
Was this review helpful? Report this review
Very good with many capabilities
) 1 of 1 people found this review helpful.
It`s a gift to my son,he is finding the calculator superb.He is a student in University(Electrical engineering)
Review ID: 10000000005208923
Was this review helpful? Report this review
Casio FX-991ESReview created: 12/12/07
by:
) 1 of 1 people found this review helpful.
I have bought the calculator so that i can use it for my orindary level exams and later for the advanced maths. I like its features and its large display which could show the fractions (for example) with the numbers on top of each other. The only two things i don't really like are that there are two less variables than other calculators by Casio and that the manual is on a large sheet not a booklet. I still like the calculator very much and would still give it an excellent rating. Also, the constants and conversions could be utilised. All in all, I'm really happy with my casio fx-991ES as it makes my life easier drawing tables and solving equations etc!
Review ID: 10000000004854700
Was this review helpful? Report this review
Calcolatore scientifico CasioReview created: 08/12/07
by:
1 of 1 people found this review helpful.
Ho acquistato il calcolatore per mio figlio di 15 anni che lo utilizza per il liceo scientifico . Rispetto a prodotti similari acquistabili nei negozi in Italia c'è stato un risparmio pari al 70 % circa (comprese le spese di spedizione).
Il calcolatore funziona benissimo .
Inolter sul sito della Casio è possibile scaricare le istruzioni d'uso in qualsiasi lingua .
Il calcolatore funziona benissimo .
Inolter sul sito della Casio è possibile scaricare le istruzioni d'uso in qualsiasi lingua .
Review ID: 10000000004792495
Was this review helpful? Report this review
Good reliable calculator.1 of 1 people found this review helpful.
This is a good basic scientific calculator, very easy to use. Bought it to help me with my exam. The only reason i rated it as good is that user guide is printed on a big folded sheet of paper, would have been more useful if it was in a book format.
Review ID: 10000000004449483
Was this review helpful? Report this review
Casio FX-991ES Scientific Calculator1 of 1 people found this review helpful.
This was purchased for my 13 yr old son who is very pleased with the calculator, who uses it for school; it can do so much more than the standard scientific ones, it appears, as I have to go on what he says!
Well worth the money
Well worth the money
Review ID: 10000000004286642
Was this review helpful? Report this review
Excellent super fast delvieryReview created: 05/11/09
by:
farhad1384 ( 2 )
IT WAS VERY GOOD DEAL.
I'M VERY HAOOY TO DEAL WITH YOU HOPE WE CAN DO BUSINESS AGAIN VERY SOON.
MANY THANKS AGAIN FOR YOUR EXCELLENT SUPER FAST DELIVERY !!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!
I'M VERY HAOOY TO DEAL WITH YOU HOPE WE CAN DO BUSINESS AGAIN VERY SOON.
MANY THANKS AGAIN FOR YOUR EXCELLENT SUPER FAST DELIVERY !!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!
Review ID: 10000000014103598
Was this review helpful? Report this review
A level CalculatorReview created: 01/11/09
by:
It will be the right tool to avoid lost non value time and help me concentrate on true Maths. The display gives full graphic text hence it avoids any mis interpretation of the answer. Is gives results in sird form avoiding approximations.
Review ID: 10000000014031723
Was this review helpful? Report this review
calculatorReview created: 22/10/09
by:
excellent and speedy delivery....just hope i can do my sums now..lol
thanks great seller. I would highly recommend you buy from these.
thanks great seller. I would highly recommend you buy from these.
Review ID: 10000000013946731
Was this review helpful? Report this review
simply perfect!Review created: 17/10/09
by:
I decide to buy it because is a very cheap product and,i have to say that the product are in my house yet and it is totally new, with a care packaging and fast shipping.i am so happy because in a market the price is highter
Review ID: 10000000013905478
Was this review helpful? Report this review
Best cheap calculatorReview created: 14/10/09
by:
Everyone at college and school appears to have the black casio but this one (silver) has about 50 more functions available. If you about to get into higher maths and require to work out quadratic equations or complex numbers, this calculator can do this for you. Obviously you still need to show your working for extra marks, but if you need confidence you have the correct answer, then it's obvious then. Another good point is that this has dual power. Solar and battery. Enjoy.
Review ID: 10000000013879541
Was this review helpful? Report this review
Excellent Calculator!I bought this calculator for my brother to use in his high school maths class. I loved the simple design and the large display screen - it really is excellent value for money. Casio is a brand name that I trust and this particular model includes a sliding case which protects the screen etc when it is at the bottom of a school bag with textbooks piled on top of it! I recommend this product to anyone studying maths at high school, college or university level.
Review ID: 10000000013872304
Was this review helpful? Report this review
Casio FX-991ES Scientific CalculatorGreat calculator. Beat any high street shop price and would recommend this seller to other students.
Review ID: 10000000013784429
Was this review helpful? Report this review
Our Favourite Calculator!Review created: 23/09/09
by:
2 Years after we bought this calculator for our eldest daughter, we have bought an identical one for her sister when she started secondary school.
We think that this is the top of the range of the "normal", non-specialized calculators in the market. It is easy to use and the natural textbook display is brilliant, especially if your child is still learning how to do specific calculations: it displays the calculations exactly as it is written in the books, which makes it easier to spot mistakes and learn from these mistakes.
The calculator is sophisticated enough to grow with your child and while in school (and further on) they will not need another calculator.
The calculator both works with batteries and with solar power, which makes sure it is always ready to use.
I really can't think of anything that I would like to change, I can fully recommend this calculator!
We think that this is the top of the range of the "normal", non-specialized calculators in the market. It is easy to use and the natural textbook display is brilliant, especially if your child is still learning how to do specific calculations: it displays the calculations exactly as it is written in the books, which makes it easier to spot mistakes and learn from these mistakes.
The calculator is sophisticated enough to grow with your child and while in school (and further on) they will not need another calculator.
The calculator both works with batteries and with solar power, which makes sure it is always ready to use.
I really can't think of anything that I would like to change, I can fully recommend this calculator!
Review ID: 10000000013600268
Was this review helpful? Report this review
Lords of CalculatorsThe only bad thing about this Sifi Calculator is that it does so much you need a lot of time to read up the User Guide to find out how to get the best out it.
Looks are nice and slim good Hard cover etc.
good layout
If you are looking for a calculator that does it all Look no more it is this Casio FX-991ES
if your looking for something just to add Dont bother your will never know how to get it to work LOL
Looks are nice and slim good Hard cover etc.
good layout
If you are looking for a calculator that does it all Look no more it is this Casio FX-991ES
if your looking for something just to add Dont bother your will never know how to get it to work LOL
Review ID: 10000000013504333
Was this review helpful? Report this review
A calculated riskMy daughter needed a calculator for school, and after a bit of time researching and discussing it with her we decided to go with Casio. (This seems to be the standard in most schools) I came across this fx991 while looking for the fx83 and thought the extra features (almost double) for the same money was too good to turn down. I have to say I’m very impressed with the simplicity this calculator handles complex calculations, and I’ll be very surprised if it doesn’t have a function that’s needed in the future.
Review ID: 10000000012756208
Was this review helpful? Report this review
Casio FX-991ES Scientific CalculatorExceptional calculator. Its the ideal calculator for anyone doing gcse/alevel or even university maths.
Review ID: 10000000012706597
Was this review helpful? Report this review
Casio FX-991ES Scientific CalculatorReview created: 07/07/09
by:
Great Product, Casio have always provided easy to use and reliable calculators and this model is no different.
Review ID: 10000000012658389
Was this review helpful? Report this review
iphone guideReview created: 18/05/09
by:
The Free iPhone Guide
To get yourself a free iPhone all you have to do is follow the 3 easy steps:
Step 1 : Sign up for a free iPhone
Sign up at the link below to get your free iPhone. We recommend this free iPhone site because it's been TRIED and TESTED to work.
http://apple.freebiejeebi
You can choose other prizes like free consoles from this site too! Make sure you use a real email address. Use your real details when you sign up so that the company knows where to send your iPhone! Remember that they have been proven legitimate, so will send you your free iPhone if you do everything legitimately!
Step 2 : Try an advertiser's offer
Basically all you need to do in this step is complete one of the offers, this is where the freebie site make their money, if you complete an offer then the freebie site will recieve commission for it. So if you complete Coral which will only cost you £5 to complete, the freebie site gets £25 from Coral. The two best offers are Lovefilm Free DVD rental (rent two DVD's, keep them for about 2 days, send them back and then cancel the trial) and Coral (bet £5 on a sport). I would reccommend you do Coral as it credits in an hour and is really simple to do, Lovefilm however can become complicated and takes up to 2 weeks to credit! You can also try one of the other offers, most are gambling offers. Don't skip this step! You must complete this step to get your free iPhone!
Step 3 : Refer some friends
This part is a lot easier than it seems, especially now with free iPhone sites getting so popular. There's lots of people online who want a free iPhone too, so start referring them! You only need to get a few signups before you'll be finished. You can ask your friends or your online buddies. I already got a free PS3, Wii, and XBOX Elite without even having to ask my friends for help - there's lots of people online who want a free iPhone like you! One of the easiest ways to get a referral is to do a favour for a friend and ask them to sign up in return. That way, you both can get a free iPhone!
Basic rules
Don't break these rules! This is the only reason that you won't get your free iPhone, so make sure you follow these rules!
- One account per household - don't use a public computer to sign up!
- Use real information - this is a proven legitimate site and they will not give out your information.
- Only complete each offer once! You cannot complete the same offer again, even for different freebies.
- Don't try to cheat the system. This site has been proven legitimate, and they will catch you if you try to cheat. If you do everything legitimately, by following this guide, you will get a free iPhone!
Thats all, just follow my guide and you will have your free iPhone in no time
To get yourself a free iPhone all you have to do is follow the 3 easy steps:
Step 1 : Sign up for a free iPhone
Sign up at the link below to get your free iPhone. We recommend this free iPhone site because it's been TRIED and TESTED to work.
http://apple.freebiejeebi
You can choose other prizes like free consoles from this site too! Make sure you use a real email address. Use your real details when you sign up so that the company knows where to send your iPhone! Remember that they have been proven legitimate, so will send you your free iPhone if you do everything legitimately!
Step 2 : Try an advertiser's offer
Basically all you need to do in this step is complete one of the offers, this is where the freebie site make their money, if you complete an offer then the freebie site will recieve commission for it. So if you complete Coral which will only cost you £5 to complete, the freebie site gets £25 from Coral. The two best offers are Lovefilm Free DVD rental (rent two DVD's, keep them for about 2 days, send them back and then cancel the trial) and Coral (bet £5 on a sport). I would reccommend you do Coral as it credits in an hour and is really simple to do, Lovefilm however can become complicated and takes up to 2 weeks to credit! You can also try one of the other offers, most are gambling offers. Don't skip this step! You must complete this step to get your free iPhone!
Step 3 : Refer some friends
This part is a lot easier than it seems, especially now with free iPhone sites getting so popular. There's lots of people online who want a free iPhone too, so start referring them! You only need to get a few signups before you'll be finished. You can ask your friends or your online buddies. I already got a free PS3, Wii, and XBOX Elite without even having to ask my friends for help - there's lots of people online who want a free iPhone like you! One of the easiest ways to get a referral is to do a favour for a friend and ask them to sign up in return. That way, you both can get a free iPhone!
Basic rules
Don't break these rules! This is the only reason that you won't get your free iPhone, so make sure you follow these rules!
- One account per household - don't use a public computer to sign up!
- Use real information - this is a proven legitimate site and they will not give out your information.
- Only complete each offer once! You cannot complete the same offer again, even for different freebies.
- Don't try to cheat the system. This site has been proven legitimate, and they will catch you if you try to cheat. If you do everything legitimately, by following this guide, you will get a free iPhone!
Thats all, just follow my guide and you will have your free iPhone in no time
Review ID: 10000000012071182
Was this review helpful? Report this review
Ready to share your opinion with others? Write a Review
About eBay | Announcements | Safety Centre | Partner Centre | VeRO: Protecting Intellectual Property | Policies | Feedback Forum | Site Map | Help | |
Copyright © 1995-2009 eBay Inc. All Rights Reserved. Designated trademarks and brands are the property of their respective owners. Use of this Web site constitutes acceptance of the eBay User Agreement and Privacy Policy.
| |
