A car is moving with speed of 150   km   h - 1 and after applying the brake it will move 27  …

In both cases, the final velocity is zero. Using equation of motion for constant acceleration

$v^2=u^2+2as$

$\Rightarrow 0^2-u^2=-2a\left(27\right) ...\left(1\right)$

$\Rightarrow 0^2-{\left(\frac{u}{3}\right)}^2=-2a{s}^{\text{'}} ...\left(2\right)$

From $\left(1\right)$ and $\left(2\right)$,

$2a\left(27\right)=9\left(2a{s}^{\text{'}}\right)$

$\Rightarrow s^{\text{'}}=3 \mathrm{m}$