Foundation June 2019 Paper 1 Q22
22 There are only blue cubes, red cubes and yellow cubes in a box.
The table shows the probability of taking at random a blue cube from the box.
| Colour | blue | red | yellow |
|---|---|---|---|
| Probability | 0.2 |
The number of red cubes in the box is the same as the number of yellow cubes in the box.
(a) Complete the table. (2)
There are 12 blue cubes in the box.
(b) Work out the total number of cubes in the box. (2)
| Answer | Mark | Mark scheme |
|---|---|---|
| 0.4, 0.4 | P1 | for process to find sum of unknown probabilities, eg \(1 - 0.2\ (= 0.8)\) |
| A1 | oe |
Additional guidance
For the P1: Award mark for any two probabilities given that sum to 0.8, eg given in the table
For the A1: Accept any equivalent fraction or 40%
| Answer | Mark | Mark scheme |
|---|---|---|
| 60 | P1 | for complete process to find total number of cubes, eg \(12 \div 0.2\) or \(12 \times 5\) or \((\text{``}0.4\text{''} \div 0.2) \times 12 + (\text{``}0.4\text{''} \div 0.2) \times 12 + 12\) OR states \(0.1 = 6\) or \(0.4 = 24\) |
| A1 | cao |