contestada

If Dr. Suzuki rides his bike to his​ office, he averages 9 miles per hour. If he drives his​ car, he averages 27 miles per hour. His time driving is one third hour less than his time bicycling. How far is his​ office?

Respuesta :

jushmk
Speed
Riding speed = 9 mph
Driving speed = 27 mph

Time
If x hours is the time taken when riding, (x - 1/3) hours  is the time taken when driving.

Distance in both instances is the same, D= Speed * time

Therefore,
9*x = 27(x-1/3)
9x = 27x - 27/2
9x = 27x - 9
(9-27)x = -9
-18x = -9
x = 9/18 = 1/2 hours

Distance, D = 1/2 *9 = 4.5 miles