Higher November 2019 Paper 2 Q16
16
(a) Show that \(\quad a\%\) of \(b = b\%\) of \(a\) [1 mark]
(b) Rosie says,
“160% of 40 = 140% of 60 because \(a\%\) of \(b = b\%\) of \(a\)”
Is she correct?
Tick a box.
- Yes
- No
Give a reason for your answer. [1 mark]
| Answer | Mark | Comments |
|---|---|---|
| \(\dfrac{a}{100} \times b = \dfrac{b}{100} \times a\) | B1 | oe eg both are equal to \(\dfrac{ab}{100}\) |
Additional guidance
| \(ab = ba\) | B0 |
| Only numerical example(s) | B0 |
| Answer | Mark | Comments |
|---|---|---|
| No and valid reason | B1 | eg No and it should be (160% of 40 =) 40% of 160 or No and it should be 60% of 140 (= 140% of 60) or No and \(160 \ne 60\) or No and \(40 \ne 140\) or No and 64 and 84 |
Additional guidance
| If neither box is ticked condone if No is clearly stated in working lines | |
| Yes or both boxes ticked | B0 |
| No and the \(a\)s aren’t the same | B1 |
| No and the \(b\)s aren’t the same | B1 |
| No and \(160 \ne 140\) | B0 |
| No and \(40 \ne 60\) | B0 |
| No and \(a\) values change from 160 to 140 | B0 |
| No and \(b\) values change from 40 to 60 | B0 |
| No and 96 and 84 | B0 |
| No and they give different answers | B0 |