Question

On their way to work, Andrew passes 15 sets of traffic lights and Pauline passes 10 sets of traffic

lights. One morning Andrew was stopped by 12 red traffic lights. How many green traffic lights would
Pauline need to pass through to have the equivalent ratio of red to green traffic lights as Andrew?

Answer 1

Explanation:

ndrew red to green ratio = 12:3 = 4:1

because 12 were red so 3 were green

Pauline to Andrew: x:(10-x) = 4:1

x(1) = 4(10-x)

x = 40 - 4x

5x = 40

x = 8

Pauline red to green ratio: 8:2

2 green lights, 8 red lights (hope its help you :) )