(i)[3]
Find the values of $a$ and $b$.
(ii)[3]
On graph paper, draw a histogram to show Robert’s times.
Mathematics 9709 · AS & A Level · Continuous random variables
Continuous random variables — practice question
Robert works part-time delivering newspapers. On several days, he recorded the time taken to complete his job, correct to the nearest minute. He used his results to complete the table below; the two missing entries are shown as $a$ and $b$.