4400 Higher June 2010 Paper 4 Q3
3 A spinner can land on red or blue or yellow.
The spinner is biased.
The probability that it will land on red is 0.5
The probability that it will land on blue is 0.2
(a) Imad spins the spinner once.
Work out the probability that it will land on yellow. (2)
Work out the probability that it will land on yellow. (2)
(b) Janet spins the spinner 30 times.
Work out an estimate for the number of times the spinner will land on blue. (2)
Work out an estimate for the number of times the spinner will land on blue. (2)
| Scheme | Marks |
|---|---|
| 1 − (0.5 + 0.2) (= 1 − 0.7) | M1 |
| 0.3 oe | A1 |
| (2) |
Notes
A1: decimals, fractions % ok.
| Scheme | Marks |
|---|---|
| 30 × 0.2 | M1 |
| 6 | A1 |
| (2) | |
| (4 marks) |
Notes
A1: cao 6/30 = M1A0