Question

There were three parts to Rita's race. She ran the first part, which was 4/9

of the total distance, in 20 minutes. She ran the second part, which was 2/5
of the remaining distance, in 12 minutes. She finally ran the third part in 15 minutes at a speed of 300 meter per minute.
How long was the second part of the race? What was Rita's speed in that section of the race?

Answer 1

Hello!

d₁ = distance covered in Part 1

d₂ = distance covered in Part 2

d₃ = distance covered in Part 3

Distance in Part 2 :

⇒ d₃ = 15 x 300 = 4500 m

⇒ d₂ = 2/5d₃

⇒ d₂ = 2/5 x 4500

⇒ d₂ = 1800 meters

Speed in Part 2 :

⇒ v₂ = 1800 m / 12 min

⇒ v₂ = 150 meters per minute