A man left his house at 10: 15a. m. and reached a town 30km away at 10: 55a. m. What was his average speed for the journey?

Sagot :

speed = distance/time
to solve for time, subtract 10:55 - 10:15 = 40 min
so he traveled for 40 min

sonvert km to meter and min to seconds
s = 30km/40 min (1000m/1km) (1min/60s)
cancel the units
s = 30(1000m)/40(60s)
s = 30000m/2400s
s =12.5 m/s