Question

20 runners were faster than Colby in a race. If 25% of the runners were faster than Colby, what was the total number of runners in the race? 75, 80, 45, 100

Answer 1

It is given that 20 runners were faster than Colby and that they were 25% of the runners.

It is required to find the total number of runners in the race.

Let the total number of runners be x.

Since 25% of the runners are 20 in number, it follows that:

`\begin{gathered} 25\%* x=20 \\ \Rightarrow(25)/(100)x=20 \\ \Rightarrow(1)/(4)x=20 \\ \text{ Multiply both sides by }4: \\ \Rightarrow4*(1)/(4)x=4*20 \\ \Rightarrow x=80 \end{gathered}`The total number of runners in the race is 80.