A discrete random variable X X\,X has the probability distribution:
| xxx | 0 | 1 | 2 | 3 |
| P(X=x)P(X=x)P(X=x) | 0.1 | aaa | 0.4 | bbb |
Where a a\,a and b b\,b are constants.
The cumulative distribution F(x)F(x)F(x) of X X\,X is given below.
| xxx | 0 | 1 | 2 | 3 |
| F(x)F(x)F(x) | ccc | ddd | 0.72 | eee |
Where ccc, d d\,d and e e\,e are constants.
Verify that a=0.22a=0.22a=0.22, b=0.28b=0.28b=0.28, c=0.1c=0.1c=0.1, d=0.32d=0.32d=0.32 and e=1e=1e=1.
215 exam-style questions on Edexcel A Level Maths Statistical Distributions, covering 6.1 Probability Distributions, 6.2 The Binomial Distribution, and 6.3 Cumulative Probabilities. Each one has a worked solution and a mark scheme showing where the marks go.