Foundation November 2024 Paper 1 Q9
9 A number is picked at random from the first three positive odd numbers.
A number is picked at random from the first four prime numbers.
The two numbers are multiplied to get a score.
(a) Complete the table. [4 marks]
| prime | |||||
| \(\times\) | 2 | 3 | 7 | ||
|---|---|---|---|---|---|
| odd | 1 | ||||
| 5 | 15 | ||||
(b) What is the probability that the score is a square number?
Give your answer as a fraction. [2 marks]
| Answer | Mark | Comments |
|---|---|---|
| 3 in left column | B1 | |
| 5 in top row | B1 | |
| All products correct | B2ft | ft their 3 and their 5 B1ft 3 to 10 correctly evaluated products |
Additional guidance
If their 3 is 0, 1 or 5, do not consider those products
If their 5 is 0, 2, 3 or 7, do not consider those products
| Answer | Mark | Comments |
|---|---|---|
| \(\dfrac{\text{their number of square numbers}}{\text{their number of completed cells}}\) | B2ft | oe fraction ft their table even if incomplete B1ft their number of square numbers as a numerator or their number of completed cells as a denominator or square numbers identified on their grid or in working |
Additional guidance
ft must produce a non-zero probability to score
Ignore attempt to simplify or convert if correct fraction seen