Paper 7 OCTOBER/NOVEMBER 2002 MATHEMATICH (9709/7) A Levels
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The number of adult customers arriving in a shop during a 5-minute period is modelled by a random variable with distribution $Po\left( 6 \right)$. The number of child customers arriving in the same shop during a 10-minute period is modelled by an independent random variable with distribution $Po\left( {4.5} \right)$.
a) Find the probability that during a randomly chosen 2-minute period, the total number of adultand child customers who arrive in the shop is less than…