RRB Group D 10-Oct-2018 Shift 2 Solved Paper

Complete work is done in 20 days.
So, 20 days . $\to 1$ work
10 days $\to \frac{1}{2}$ work
$\therefore$ Remaining work after 10 days $=1-\frac{1}{2}=\frac{1}{2}$
Now, 15 persons complete a job in 20 days
So, 15 persons $\to 20$ days
5 persons $\to 20\times 3$ days
Thus 10 persons take $\frac{20\times 3}{2}$ days $=30$ days
$\therefore$ Work done in 5 days $=\frac{5}{30}=\frac{1}{6}$
So remaining work $=\frac{1}{2}-\frac{1}{6}=\frac{1}{3}$
Days require to complete $\frac{1}{3}$ th of the work $=\frac{1}{3}\times 20\times 3=20$ days
Thus total days required to complete the job $=10+5+20=35$ days