Question 519438
distance A to B = x
speed of Truck B = y
speed of truck A = y+10

Truck B
x/y = 5
x=5y

Truck A
x/(y+10)= 4 
x=4(y+10)
x=4y+40
equate x

5y=4y+40
y=40 mph, speed of truck B
Truck A speed = 50 mph

plug y in x=5y
x= 5*40 =200 miles

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