Foundation November 2023 Paper 1 Q21
21 The mean length of 5 sticks is 4.2 cm.
Nawal measured the length of one of the sticks as 7 cm.
(a) Work out the mean length of the other 4 sticks. (3)
Nawal made a mistake.
The stick was not 7 cm long.
It was 17 cm long.
(b) How does this affect your answer to part (a)? (1)
| Answer | Mark | Mark scheme |
|---|---|---|
| 3.5 | P1 | for a process to find the total length of the 5 sticks, eg \(4.2 \times 5\ (= 21)\) or for forming an equation, eg \(\dfrac{7 + 4x}{5} = 4.2\) |
| P1 | for complete process to find the mean eg \((\text{``}21\text{''} - 7) \div 4\) | |
| A1 | oe |
| Answer | Mark | Mark scheme |
|---|---|---|
| Explanation | C1 | for explanation Acceptable examples it reduced the mean my answer will be less the answer will be 1 it will be 2.5 less Not acceptable examples the mean will be more my answer will change it would decrease the lengths of the other sticks |
Additional guidance
If figures are given as part of the answer they must be correct, but can allow ft.