In a flat race, A beats B by 15 metres and C by 29 metres. When B and C run over the course together, B wins by 15 metres. Find the length of the course
Let x be the length of the course
A beats B by 15 metres and C by 29 metres
=> When A runs x metre, B runs $\left(x-15\right)$ metre and C runs $\left(x-29\right)$ metreWhen B and C run over the course together, B wins by 15 metres
=> when B runs x metre, C run $\left(x-15\right)$ metre
$\text{=> when B runs 1 metre, C run }\dfrac{x-15}{x}\text{ metre}$
$\text{=> when B runs $\left(x-15\right)$ metre, C run }\dfrac{x-15}{x} \times (x-15) = \dfrac{(x-15)^2}{x}\text{ metre}$
$\text{i.e., }(x-29) = \dfrac{(x-15)^2}{x}$
$\Rightarrow x^2 - 29x = x^2 - 30x + 225$
$\Rightarrow - 29x = - 30x + 225 $
$\Rightarrow x = 225$