The cost of 3 rackets and 2 squash balls is £26.57. The cost of 5 rackets and 7 squash balls is £52.90.
Work out the cost of
a) a squash ball.
b) a racket.

The random variable x is the number of occurrences of an event over an interval of ten minutes. it can be assumed that the probability of an occurrence is the same in any two-time periods of an equal length. it is known that the mean number of occurrences in ten minutes is 5.3. the appropriate probability distribution for the random variable