EDEXCEL GCSE MATHS · FOUNDATION & HIGHER
Exam Practice: Place Value and Estimating
Place value and estimating · Number · Lesson 2 of 7 · 11 marks · 25 minutes
Name Date
Answer all questions. Show your working. Questions 1 to 5 are non-calculator.
Question 1 NON-CALCULATOR [2 marks]
Using the information that 38 × 142 = 5396, write down the value of (a) 3.8 × 14.2 (b) 5396 ÷ 1.42
Question 2 NON-CALCULATOR [1 mark]
Round 0.070 49 to 3 significant figures.
Question 3 NON-CALCULATOR [3 marks]
Work out an estimate for (3.78 × 48.2)/0.52
Question 4 NON-CALCULATOR [1 mark]
Is your answer to the last question an overestimate or an underestimate? Give a reason for your answer.
Question 5 NON-CALCULATOR [2 marks]
Estimate the value of √70. Give your answer to 1 decimal place.
Question 6 CALCULATOR [2 marks]
(a) Use your calculator to work out (6.2 + 3.84)²/(√0.7). Write down all the figures on your calculator display. (b) Write your answer to part (a) correct to 4 significant figures.
Answers
Check your answer only once you have written one.
Question 1 [2 marks]
(a) 53.96 (b) 3800
▸ (a) 53.96 B1
▸ (b) 3800 B1
Question 2 [1 mark]
0.0705
▸ 0.0705 B1
Question 3 [3 marks]
(4 × 50)/0.5 = 200/0.5 = 400
▸ At least two of the numbers rounded correctly to 1 s.f. (4, 50, 0.5) M1
▸ 200 ÷ 0.5 or 4 × 100 or equivalent M1
▸ 400 A1
Question 4 [1 mark]
An overestimate: 3.78 and 48.2 were both rounded up, making the top bigger, and 0.52 was rounded down, and dividing by a smaller number gives a bigger answer.
▸ Overestimate, with a correct reason referring to the rounding C1
Question 5 [2 marks]
64 = 8² and 81 = 9², so √70 is between 8 and 9. 70 is 6 of the 17 steps from 64 to 81, so √70 ≈ 8.4.
▸ 8² = 64 and 9² = 81 seen, or √70 stated to be between 8 and 9 M1
▸ Answer in the range 8.3 to 8.4 A1
Question 6 [2 marks]
(a) 120.4809562 (b) 120.5
▸ (a) 120.48095… (at least 6 figures) B1
▸ (b) 120.5, follow through from (a) B1