The bus driver drives an average of 2 hours each day, 5 days a week. From Monday to Wednesday he drove at an average speed of 12 kilometers per hour, and from Thursday to Friday at an average speed of 9 kilometers per hour. How many kilometers did the driver travel during these 5 days?
From Monday to Wednesday, there are 3 * 2 = <T>multiply(3, 2)=6 hours of work.
During this time the driver drove 6 * 12 = <T>multiply(6, 12)=72 kilometers.
On Thursday and Friday, there are 2 * 2 = <T>multiply(2, 2)=4 hours of work in total.
During this time the driver drove 4 * 9 = <T>multiply(4, 9)=36 kilometers.
So in total, the driver traveled 72 + 36 = <T>add(72, 36)=108 kilometers during these five days.
