(a)[1]
State the class interval that contains the median time.
(b)[4]
Calculate an estimate for the mean time.
(c(i))[1]
He says that it is not possible to work out the range of the times. Explain why he is correct.
(c(ii))[2]
He draws a pie chart to represent this information. Calculate the sector angle for the interval $65 < t \leq 70$ minutes.
(d)[1]
A girl is selected at random. Find the probability that she took more than 100 minutes to complete the essay.
(e(i))[2]
Work out the probability that both took 65 minutes or less to complete the essay.
(e(ii))[3]
One girl took 65 minutes or less and the other took more than 100 minutes.
(f)[3]
Fill in the table below.