Question 335000
Let the distance = x miles
Speed = 10mph
Time taken = Distance / speed = x/10 hours

Returning time taken = x/25

x/10 - x/25 = 1.5 

MULTIPLY BY 50 both sides

5x - 2x = 75
3x = 75
x = 25 miles

Time taken = 25/10 = 2.5 hours ANSWER