Foundation November 2021 Paper 1 Q8
8.
(a)
Put one pair of brackets in each calculation to make it correct.
(i) \(3 \times 4 + 1 \times 2 = 30\) [1]
(ii) \(50 - 36 \div 2 \times 3 = 21\) [1]
(b)
Callum is working out \((41 - 29{\cdot}5)^2\).
He estimates the answer to be 700.
Is Callum’s answer a good estimate?
Yes ☐ No ☐
Show how you decide. [2]
| Scheme | Marks | Comments |
|---|---|---|
| (i) \(3 \times (4 + 1) \times 2 = 30\) | B1 | |
| (ii) \((50 - 36) \div 2 \times 3 = 21\) | B1 |
| Scheme | Marks | Comments |
|---|---|---|
| No and valid supporting evidence e.g. ‘(40 – 30)2 is about 100’ or ‘41 – 29.5 = 11.5 ≈ 12 so it is about 144’ or ‘112 is 121’ | E2 | Allow e.g. ‘No and the answer is about 100’ for 2 marks E1 for No and partial evidence which includes both the difference and squaring e.g. sight of (40 – 30)2 or ‘41 – 29.5 = 11.5 and 11.52 is a lot less than 700.’ NB if ‘yes’ is indicated then E0 |
| (4) |