MATH
posted by Anonymous on .
Trains A and B are traveling in the same direction on parallel tracks. Train A is traveling at 40 miles per hour and train B is traveling at 60 miles per hour. Train A passes a station at 8:20pm. If train B passes at the same station at 8:35 p.m at what time will train B catch
up to train A.

when B gets to station, A is this far ahead:
distance: 1/4 hr*40mph= 10 miles.
So, to make up that 10 miles, B is traveling at a relative velocity of 20 mph (6040)
time= distance/velocity= 10/20 hr 
so, add that time, 30 min, to 8:35

In 1994, the life expectancy of males in a certain country was 73.8 years. In 2000, it was 77.4 years. Let E represent the life expectancy in year t and let t represent the number of years since 1994