Higher November 2019 Paper 2 Q17
17 A packet contains 80 sweets.
The flavour of each sweet is lemon, orange or apple.
A sweet is taken at random.
(a) P(lemon or orange) \(\leqslant\) 0.85
Work out the minimum possible number of apple sweets in the packet. [2 marks]
(b) P(lemon or apple) < 0.71
There are 31 lemon sweets.
Work out the maximum possible number of apple sweets in the packet. [2 marks]
| Answer | Mark | Comments |
|---|---|---|
| 12 | B2 | B1 \((1 - 0.85) \times 80\) or \(0.15 \times 80\) or \(0.85 \times 80\) or 68 |
Additional guidance
| For B1 allow oe calculations eg \(17 \times 4\) | B1 |
| Answer | Mark | Comments |
|---|---|---|
| 25 | B2 | B1 \(0.71 \times 80\) or 56.8 or 56 or \((1 - 0.71) \times 80\) or \(0.29 \times 80\) or 23.2 or 24 or \((0.71 - 0.3875) \times 80\) or \(0.3225 \times 80\) or 25.8 |
Additional guidance
| For B1 allow oe calculations eg \(\left(0.71 - \dfrac{31}{80}\right) \times 80\) | B1 |
| Answer only 26 | B0 |