Eddie and Ellen use a calculator to work out 431.114.3+3.82\displaystyle \frac{431.1}{14.3 + 3.8^2}14.3+3.82431.1
Eddie's answer is 1.5
Ellen's answer is 15
One of those answers is correct.
Use approximations to find out which answer is correct.
Practise Oxford AQA IGCSE Maths Estimating with exam-style questions for Core and Extended tier. 15 questions, matched to the Oxford AQA IGCSE Maths (9260) specification and written in Paper 1 and Paper 2 (Core: 1C and 2C; Extension: 1E and 2E) style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.