Given :
Michaela runs to the end of her street and back in 90 s.
Her brother, Jacob, walks to the end of the street and back in 3 min.
They both run or walk for the same amount of time, but Michaela makes 5 more trips than Jacob.
To Find :
How many times did each person go to the end of the street and back.
Solution :
Let, they both walk for T seconds.
Number of rounds Michaela walk is, n₁ = T/90 .
Number of rounds Jacob walk is, n₂ =T/180 .
It is given that :
n₁ = n₂ + 5
T/90 + T/180 = 5
( T/90 + T/180 ) × 180 = 5×180
2T + T = 900
3T = 900
T = 300 s
So, n₁ = 300/90 = 3
n₂ = 1
Hence, this is the required solution.