Question 411874
let speed of red car be x mph
speed of blue car = x+55 mph
catch up distance = 1/2 mile = 
catch up time = 70 seconds = 70/3600 hours= 7/360 hours

s= d/t
s= (3/2 ) / (7/360)
s=3/2 * 360/7
s=540/7
x+55 = 540/7
7x+385=540
7x=540-385
7x=155
/7
x=22.14
Speed of red car = 55+22.14 = 77.14 mph