After 3 hours, the faster car will be 75 miles ahead of the slower car.
Step-by-step explanation:
Given, 
Speed of first car = 56 miles per hour 
Speed of second car = 31 miles per hour 
Let, 
x be the number of hours.
Distance covered by first car = Speed * time = 56x
Distance covered by second car = 31x 
According to given statement; 
Difference between distance covered by both cars = 75 miles 
Distance of faster car - Distance of slower car = 75 miles 

Dividing both sides by 25

After 3 hours, the faster car will be 75 miles ahead of the slower car.
Keywords: subtraction, division 
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