This assumes that the 2 girls are traveling in the same direction! Are they traveling FROM Home or TO Home? Gotta figure that out.
If FROM Home:
Monica's trip is defined by Mon(t) = 400 mi + (50 mph)t, and
Marcia's trip is defined by Mar(t) = 300 mi + (30 mph)t
We must set these equal to one another and try to solve for time, t:
400+50t = 300+30t then 100= -20t. This results in a negative time answer, which is not possible.
Therefore, we must assume that the 2 girls are traveling TO Home.
Monica's trip is defined by Mon(t) = 400 mi - (50 mph)t, and
Marcia's trip is defined by Mar(t) = 300 mi - (30 mph)t
When do they meet? Solve 400 - 50t = 300 - 30t
100 = 20t, and t = 5 hours (answer)
