Rational expression word problem

Question

don left vancouver and drove towards hope BC at a speed of 120km/h brad left hope at the same time and drove towards vancouver at a speed of 90km/h if hope is 122km from vancouver how far had they each driven when they passed each other on the highway?

Answer 1

When they reach the same spot on the road, the sum of their

distances travelled will be 122 km and each will have been

driving for the same amount of time

 

distance = rate*time

 

Don: d = 120t

Brad: d = 90t

 

120t + 90t = 122

210t = 122

t = 122/210

t = 0.581 hours

 

Don:  Distance = 120(0.581) = 69.72 km

Brad: Distance = 90(0.581) = 52.29 km

 

Rounding these to one decimal point

Don went 69.7 km and Brad went 52.3 km which adds to 122 km