9514 1404 393
Answer:
90 miles
Explanation:
Let d represent the distance to Grandma's house.
The speed going was ...
speed = distance/time
speed = d/2
The speed coming home was ...
speed = d/2.25
The difference of these speeds is 5 miles per hour:
d/2 -d/2.25 = 5
2.25d -2d = 5(4.50) . . . . . multiply by 4.50
0.25d = 22.5 . . . . . . . . . . .simplify
d = 90 . . . . . . . . . . . . . . . . multiply by 4
Grandma's house is 90 miles away.