Course home

2.4.1 Discrete distributions and the binomial

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Question 5

13%

Mustafa plays a game where he can score 0, 5, 10, 15 or 20 points.

The random variable $X$ , representing the number of points scored, has the following probability distribution, where $a\,$ and $b\,$ are constants.


$x$	0	5	10	15	20
$P (X = x)$	$a$	0.2	$b$	0.15	0.3

The probability of scoring more than 5 is three times the probability of scoring 5 or less.

Mustafa plays the game twice and adds the scores together. Each game is independent of the previous game.

Calculate the probability that the total score is 25 points.

[6]

Markscheme

2.4.1 Discrete distributions and the binomial Questions

A Level
Maths
2.4.1 Discrete distributions and the binomial

39 exam-style questions on AQA A Level Maths 2.4.1 Discrete distributions and the binomial. Each one has a worked solution and a mark scheme showing where the marks go.

2.4.1 Discrete distributions and the binomial

Question bank

2.4.1 Discrete distributions and the binomial

Easy Medium Hard

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Question 5

13%

Mustafa plays a game where he can score 0, 5, 10, 15 or 20 points.

The random variable $X$ , representing the number of points scored, has the following probability distribution, where $a\,$ and $b\,$ are constants.


$x$	0	5	10	15	20
$P (X = x)$	$a$	0.2	$b$	0.15	0.3

The probability of scoring more than 5 is three times the probability of scoring 5 or less.

Mustafa plays the game twice and adds the scores together. Each game is independent of the previous game.

Calculate the probability that the total score is 25 points.

[6]

Markscheme

2.4.1 Discrete distributions and the binomial Questions

A Level
Maths
2.4.1 Discrete distributions and the binomial

39 exam-style questions on AQA A Level Maths 2.4.1 Discrete distributions and the binomial. Each one has a worked solution and a mark scheme showing where the marks go.