Posted by Catherine on Wednesday, January 12, 2011 at 12:01am.
Amtrail trains provide efficient, nonstop transportation between Los Angeles and San Diego. Train A leaves Los Angeles headed toward San Diego at the same time that Train B leaves San Diego headed for Los Angeles, traveling on parallel tracks. Train A travels at a constant speed of 84 miles per hour. Train B travels at a constant speed of 92 miles per hour. The two stations are 132 miles apart. How long after they leave their respective stations do the trains meet?

MATH  Don H, Wednesday, January 12, 2011 at 1:11am
let x be the time taken for them to meet. D=v*t D1=84t, D2=92t The sum of the distances is 132miles.
Thus 84t + 92t = 132
and 176t = 132
or t = 132/176
t =3/4 hours
check:
84(3/4) + 92(3/4)
= 63 + 69
=132 miles 
MATH  t, Tuesday, January 8, 2013 at 5:07pm
7 hrs