Answer
55mph
Work Step by Step
Car #1 needs to pass Car#2 covering the distance of both vehicles. Car #1 is 14ft and Car #2 is 30ft. So with Car#2 moving at 55mph, how fast does Car#1 have to go to make that distance in 6 seconds?
Lets start with converting the 50mph to ft/sec.
5280 = feet in a mile
$5280*50 = 264000$ft per hour
$\frac{264000}{60} = 4400$ft per minute
$\frac{4400}{60} = 73\frac{1}{3}$ ft per second
So we need to add an additional 44ft per 6 seconds.
$\frac{44}{6} = 7\frac{1}{3}$
$ 7\frac{1}{3} + 73\frac{1}{3} = 80\frac{2}{3}$
Then we convert back to mph.
$80\frac{2}{3} * 60 = 4840$ft per min
$4840 * 60 = 290400$ft per hour
$\frac{290400}{5280} = 55$mph
