Question 1114120
The first friend runs at a speed of 8 miles per hour.
The second friend runs at a speed of 7 miles per hour. 

they left at 6 p.m. 
their houses are 20 miles apart, 

Since they are running towards each other the effective speed will be (8+7) = 15 mph

Distance = 20 miles
time they run = 20/15 =4/3 hours

They meet at 7.20 pm