Higher November 2024 Paper 2 Q7
7 Beth and Lynn each spin the same biased coin a number of times.
The table shows information about the results.
| Beth | Lynn | |
|---|---|---|
| Number of spins | 125 | 80 |
| Relative frequency of Heads | 0.32 | 0.35 |
(a) How many more Heads did Beth spin than Lynn? [2 marks]
(b) Lynn says,
“My estimate of the probability of the coin landing on Heads must be the best, because 0.35 is greater than 0.32”
Is she correct?
Tick a box.
- Yes
- No
Give a reason for your answer. [1 mark]
| Answer | Mark | Comments |
|---|---|---|
| \(125 \times 0.32\) or 40 or \(80 \times 0.35\) or 28 | M1 | oe |
| 12 | A1 |
Additional guidance
| M1 may be awarded for correct work with no answer or incorrect answer, even if this is seen amongst multiple attempts | |
| \(80 \times 0.5 = 40\) | M0 |
| Answer | Mark | Comments |
|---|---|---|
| No and valid reason involving the number of trials | B1 | eg reasons she didn’t do the most she did fewer spins Beth did more they should use all 205 spins |
Additional guidance
| Ignore irrelevant or incorrect statements alongside a correct statement as long as not contradictory | |
| eg1 No and Beth did most but she could have done more | B1 |
| eg2 No and Beth has more number of spins so there is a higher probability of landing on heads | B1 |
| eg3 No and Beth did most spins but Lynn did more | B0 |
| Allow ‘she’ to refer to Lynn unless clearly referring to Beth eg No and Because she tried 125 times however Lynn tried only 80 times | B1 |
| No and She did not do as many spins so her answer is less accurate than Beth’s | B1 |
| No and Beth spun the wheel more times. Therefore her probability would be lower | B1 |
| No and Beth spun more times so her final outcome will be higher | B1 |
| No and Beth did 125 spins and Lynn did 80 spins | B0 |
| No and Beth did 125 spins so she has more chance of being accurate | B0 |