Driving speed

Question

Sean's Camaro travels 15 mph faster than Rita's Harley. In the same time that Sean travels 156 mi, Rita travels 120 mi. find their speed?

Answer 1

t = d/v

 

Sean:

 

t = 156/v

 

Rita:

 

t = 120/u

 

v = u + 15

 

The t is the same for both.

 

120/u = 156/(u +15)

 

u/120 = (u + 15)/156

 

1.3u = u + 15

 

u = 15/(1.3 -1) = 50

 

v = u + 15 = 50 + 15 = 65

 

Sean's speed is 65 mph.

Rita's speed is 50 mph.