Afamily leaves home at 1 p. m in their vehicle. while billy asks, "are we there yet? " at 2: 30 p. m., they are 70 miles from grandma's house. when janie asks "are we there yet? " at 2: 45 p. m., they are 55 miles away. how far from grandma's house does the family live? at what time will the family arrive at grandma's?

At 2:30, they are 70 miles away, at 2:45, they are 55 miles away.
That means, in 15 minutes, they traveled 15 milesthats 1 mile per minute.
so 2:4555 miles away...at 1 mile per minute = 2:45 + 55 minutes = 
3:40. <== when they arrive at Grandma's house.

3:40 - 1:00 = 2:40it took 2 hrs and 40 minutes for the tripthats 120 + 40 = 160 minutes <== =so the family lives 160 miles from Grandma's house