Question

TWO cars leave towns 320 kilometers apart at the same time and travel toward each other. One car's rate is 20 kilometers per hour less than the other's. If theymeet in 2 hours, what is the rate of the slower car?Do not do any rounding.

Answer 1

TWO cars leave towns 320 kilometers apart at the same time and travel toward each other. One car's rate is 20 kilometers per hour less than the other's. If they

meet in 2 hours, what is the rate of the slower car?

Let

x-20 ------> One car's rate

x-----> Other car's rate

Remember that

the speed or rate is equal to divide the distance by the time

s=d/t

d=s*t

so

d1=2(x-20)

d2=2(x)

we have that

d1+d2=320

substitute

2(x-20)+2x=320

solve for x

2x-40+2x=320

4x=320+40

4x=360

x=90 km/h

and

(x-20)=90-20=70 km/h

therefore

the answer is 70 km/h