4MA0 Foundation June 2015 Paper 2R Q14
14 The diagram shows a pointer that spins about the centre of a circle.
The circle is divided into 12 equal sectors.
When the pointer spins, it is equally likely to stop in any one of the sectors.
Each sector has a number.
Andrea spins the pointer.
(a) Find the probability that the pointer stops in a shaded sector. (1)
(b) Find the probability that the pointer stops in an unshaded sector with an odd number. (1)
Andrea now spins the pointer twice and adds together the two numbers in the sectors that the pointer stops in.
The probability that the total of the two numbers is 7 or more is \(\dfrac{19}{36}\)
(c) Work out the probability that the total of the two numbers is less than 7 (2)
| Scheme | Marks |
|---|---|
| \(\dfrac{5}{12}\) | B1 |
| (1) |
Notes
B1: Accept 0.41, 0.42, 0.41(6666…)
| Scheme | Marks |
|---|---|
| \(\dfrac{4}{12}\) | B1 |
| (1) |
Notes
B1: Accept 0.33(333…), \(\dfrac{1}{3}\)
| Scheme | Marks |
|---|---|
| \(1 - \dfrac{19}{36}\) | M1 |
| \(\dfrac{17}{36}\) | A1 |
| (2) | |
| Total 4 marks |
Notes
A1: Accept 0.47(222…)