Description for Correct answer:
A's 1 day's work = \( \Large \frac{1}{2} \)

B's 1 day's work = \( \Large \frac{1}{3} \)

A's share : B's share = \( \Large \frac{1}{2} \) : \( \Large \frac{1}{3} \)

= \( \Large \frac{3}{6} \) : \( \Large \frac{2}{6} \) = 3 : 2

A's share = \( \Large \frac{3}{5} \times 6000 \) = Rs.3600

Therefore, 20% of A's share = \( \Large 3600 \times \frac{20}{100} \) = Rs.720