How many kilometers a motorist travel from 9:55 a.m to 10:15 a.m at the rate of 40 kilometers per hour?

13 1/3

Convert the time from 9:55 a.m. to 10:15 a.m. to a fraction of an hour:

20 minutes = 20/60 = 1/3 hour

Multiply the rate (40 km/h) by the time (1/3 hour):

40 km/h × 1/3 h = 40/3 km

40/3 km = 13 1/3 km

So, the motorist travels 13 1/3 kilometers.