A cricketer hit 120 runs in 150 balls during a test match.

(i) Let the cricketer score w runs in 6's.

$\therefore 20 \%$ of $120=w$

$\Rightarrow \frac{20}{100} \times 120=w$

$\Rightarrow w=24$

(ii) Let the cricketer score $x$ runs in 4 's.

$\therefore 30 \%$ of $120=x$

$\Rightarrow \frac{30}{100} \times 120=x$

$\Rightarrow x=36$

(iii) Let the cricketer score $y$ runs in 2's.

$\therefore 25 \%$ of $120=y$

$\Rightarrow \frac{25}{100} \times 120=y$

$\Rightarrow y=30$

(iv) Let the cricket $e r$ score $z$ runs in 1's.

Since, the cricketer scores the rest of the runs in 1's, we have:

$24+36+30+z=120$

$\Rightarrow z+90=120$

$\Rightarrow z=30$