Foundation November 2017 Paper 3 Q11
11 A fair spinner has 12 equal sections.
Label each section A, B, C or D so that when the arrow is spun,
the probability it lands on A is \(\dfrac{1}{6}\)
the probability it lands on B is equal to the probability it lands on C
the probability it lands on D is double the probability it lands on A.
| Answer | Mark | Comments |
|---|---|---|
| A in two sections | B1 | |
| B and C have equal number of sections and 12 sections labelled using only A, B, C or D | B1 | P(B) = P(C) \(\ne\) 0 |
| D in twice as many sections as A | B1 |
Additional guidance
| 2As, 3Bs, 3Cs, 4Ds | B1B1B1 |
| 2As, 5Bs, 5Cs B and C have equal number of sections and 12 sections labelled using only A, B, C or D | B1B1B0 |
| 2As, 4Bs, 4Cs, 2Ds | B1B1B0 |
| 2As, 2Bs, 4Cs, 4Ds | B1B0B1 |
| 2As, 4Ds | B1B0B1 |
| 2As, 4Bs, 4Cs only 10 sections labelled | B1B0B0 |
| 2As, 3Bs, 4Cs, 3Ds | B1B0B0 |
| 1A, 2Bs, 2Cs, 7Ds | B0B1B0 |
| 1A, 2Bs, 2Cs, 3Ds only 8 sections labelled | B0B0B0 |