Fiora tides her bike at 18/mi/hr then slowed down to 10mi/hr and maintains that speed. The whole trip was 121 miles and took 8.5 hrs . How long did she travel at 18mi/hr?

Answer 1

t is the time she rode 10 mph.

Then, since distance = rate * time,

121 = 18*(8.5-t) + 10*t

121 = 153 - 18t + 10t

121 = 153 - 8t

-32 = -8t

t=4

She went 18 mph for 4.5 hours , which is 81 miles

Then she went 10 mph for 4 hours which is 40 miles