SOLUTION: My brother and I walk the same route to school every day. My brother takes 40 minutes to get to school and it takes me 30 minutes. Today, my brother left 8 minutes before I did.

Question 260463: My brother and I walk the same route to school every day. My brother takes 40 minutes to get to school and it takes me 30 minutes. Today, my brother left 8 minutes before I did. How long will it take me to catch up with him?
Answer by drk(1908) (Show Source): You can put this solution on YOUR website!
This is an RTD problem. Here is a table based on the given information:
brothers . . . . . . . . rate . . . . . . . . . .time . . . . . . . . . .distance
brother . . . . . . . . . .D/40 . . . . . . . .. .T+8 . . . . . . . . . . . .D
me . . . . . . . . . . . . . D/30. . . . . . . . . .T . . . . . . . . . . . . . .D
you want to catch up to brother, so the distances must be equal.
(i)
cross multiply to get
(ii)
simplify to get
(iii)
subtracting, we get
(iv)
divide by 10D to get
(v)
You will catch up after 24 minutes.
RELATED QUESTIONS
two siblings-a brother and sister-attend the same school. Walking at constant rates the... (answered by josmiceli)

My brother and I go to the same school. My brother takes 8 minutes to walk to school, and (answered by edjones)

Two siblings attend the same school. The brother takes 40 minutes to walk home, while his (answered by ikleyn)

if i drive 20 miles to school, and it takes me 30 minutes to get here, what is my average (answered by tonyclarke)

When Dave walks to school, he averages 90 steps per minute, each of his steps are 75 cm... (answered by mananth)

On a normal day, I can walk from my house to school in three quarters of an hour. The... (answered by Simnepi)

if I walk from home to school and it takes me 38minutes how long would it take me to get... (answered by ewatrrr)

brothers harry and chris walk to school from house. the former takes 40 minutes while... (answered by jorel555)

Just like my other question, I keep coming with wrong equations, these are my final... (answered by stanbon,Mathtut)