Casio FX-85GTPLUS-SB-UT Scientific Calculator (Old Model) replaced by the new FX-85GTX

I'm old enough to remember my maths teacher, in the 1970s, showing us his newly purchased Sinclair Scientific calculator (I expect he saved a few pounds by buying it as a self-assembly kit). It was amazing then to see such a small device which could calculate sines, square roots, etc, and it must have cost around £60 then.Today the price of this Casio model is not much more than a pack of cigarettes (not that I buy them these days) - whereas in the 1970s I estimate that you could have bought perhaps 200 packets of 20 (e.g. Rothmans Kingsize) for the price of one Sinclair Scientific calculator!I bought this Casio FX-85GTPLUS for my son, who needs it for GCSE maths. He is very happy with it. It does everything he needs, it is sure to be reliable, and it arrived promptly. It's slightly larger than I expected, which is not a problem; when using it, the grey sleeve does not need to be slid down as shown in the picture.

The Casio Scientific Calculator was delivered the next day with Amazo Prime and arrived well packaged.This is a replacement purchase of the exact item I bought over two years ago from the same listing. We lost the previous one and because it is such a good calculator I repeated the order.The main use of this item is for school work and it is excellent for this purpose.It has a useful cover case which slides out and keeps the calculator clean whilst protecting it from damage.It has all the possible combinations and functions you can ever need and it is ideal for schoolwork or more advanced professional use.Unless you loose it, you won't ever need to replace it!

Had this variation of calculator for many years now and it has never let me down. Excellent battery life and solar panel charging, never runs out of juice. Only downside is a slightly complicated method of changing input methods from stat to regular etc, but instructions come in the box, even if they are fairly obscure.

Bought for myself for an upcoming maths course and came the next day with no problems and packaged well using Amazon Prime. Before swapping to this calculator, I mostly just used my iPhone calculator but obviously this allows for more deep and complex calculations. In addition, with a nice easy to read display this can show you the textbook format so you know exactly how to write your calculations on paper.It also comes with a hard protective case that you can clip onto the back when your using it so you don't damage moving around with it in your bags or pockets which is nice.I've been using it for a little under two months so far and it works great! I would recommend it to anyone.

Excellently priced calculator purchased for secondary school Y7 new starter. This model has a solar panel and battery back up, which the lower model does not have. Nice large clear display, a sliding case that you can slide on and use the calculator, so doesn't get lost. Buttons look to be long lasting (some can look like they could be picked off, but this does not). Packaging states this is suitable for GCSE Maths. Sturdy plastic, comes with instructions and has a guarantee. Very pleased!

Bought for my 13 year old son in Year 8 at school, as school recently e-mailed us saying that they would like all children to get this model of calculator or similar. Will serve him right the way through to end of GCSE's in Year 11. My daughter had the same one, and is now at the end of Year 11 and the only issue is it's been so well used some of the markings have rubbed off the keys, or part thereof. Thus why we have not passed it down and chosen to replace what has been the calculator of choice by school. My daughter is very bright and top set in maths, and this has done everything she needs to do. Worked well all these years with no issues, well made, good calculator I am told.

When it comes to calculators, other than your phone this is the best one on the market. It is easy to use and has all the features for both GCSE's and A-Levels. The design and strong despite it being plastic and the battery life is basically infinite thanks to the solar panel in the top right-hand corner of the calculator. I have been using my other one at school for two years and I am replacing it with the same one. I would not need to replace it if I hadn't lost the battery cover for my old one (my fault) and coloured it in (also my fault).

I ordered two of these on Saturday afternoon- one for each of my boys. Very impressed that they were outside or door on Sunday morning. Sadly one of them did not work (0 button not functioning) and we needed them urgently for school exams. Amazon great on replacing however although we are still waiting for the delivery of the replacement. Hence calculator itself is great and what the school recommends- but given a 3 star in the circumstances.