Foundation June 2023 Paper 2 Q15
15 Finn is asked to find the value of \(\;5 + 3^2 + 12\)
Here is his working and his answer.
\(\begin{aligned} 5 + 3^2 + 12 &= 8^2 + 12 \\ &= 64 + 12 \\ &= 76 \end{aligned}\)
Finn’s answer is wrong.
(a) Explain what Finn has done wrong in his working. (1)
(b) Write one pair of brackets in this calculation so that the answer is correct.
\(2 \times 6 - 4^2 - 14 = 10\) (1)
\(2 \times 6 - 4^2 - 14 = 10\) (1)
(c) Work out the value of \(\;x^2 + 5y\;\) when \(x = {-3}\) and \(y = 2\) (2)
| Scheme | Marks |
|---|---|
| Valid Reason | B1 |
| (1) |
Notes
B1: eg Finn added 5 and 3, but he should have squared the 3 first.
| Scheme | Marks |
|---|---|
| \(2 \times 6 - (4^2 - 14)\) | B1 |
| (1) |
Notes
B1: Brackets in correct location.
Condone correct but unnecessary brackets.
[must not be around the minus sign between the 6 and the \(4^2\)]
| Scheme | Marks |
|---|---|
| \(9 + \ldots\) or \(\ldots + 10\) or \((-3)^2 + 5 \times 2\) or \(-3 \times -3 + 5 \times 2\) | M1 |
| Correct answer scores full marks (unless from obvious incorrect working) Answer: 19 | A1 |
| (2) | |
| (4 marks) |
Notes
M1: For either 9 or 10 in the correct place or the correct substitutions (brackets around –3 squared, unless recovered)