I just need part B of this question I dont really understand

I just need part B of this question I don\'t really understand it, please help!

To decide on the number of service counters needed for stores to be built in the future, a supermarket chain wanted to obtain information on the length of time (in minutes) required to service customers. To find the distribution of customer service times, a sample of 60 customers\' service times was recorded and are shown here. Construct a stem and leaf plot for the data. (Enter numbers from smallest to largest separated by spaces. Enter NONE for stems with no values.) What fraction of the service times are less than or equal to 1 minute?

Solution

b)

Those under 1 minute are those with stems equal to 0.

Thus, there are 24 such subjectsc [first two rows].

As there are 60 customers, then the fraction of those less than 1 minute is

P(less than 1 min) = 24/60 = 2/5 or 0.4 [answer]