An express bus travels 320 miles in the same amount of time that a car travels 280 miles. the rate of the car is 8 mph less than the rate of the bus. find the rate of the bus.

Form 2 equations

distance = rate * time

for the bus:-

320 = rt where r is the rate of the bus

For the car

280 = (r - 8) t

from first equation: - t = 320/r

so substituting in secod equation:-

280 = 320 (r - 8) / r

280r = 320r - 2560

40r = 2560

r = 2560/40 = 64

rate of bus = 64 mph