Question

$50$ labourers can dig a pond in $16$ days. How many labourers will be required to dig another pond in $20$ days, which is double in size?

• A. $80$
• B. $30$
• C. $70$
• D. $20$

Answer 1

The correct option is A $80$

$50$ labourer Pond size $=x$ in $16$ days

$1$ labourer can build pond size $x$ in $50\times 16$days

$1$ labourer can build pond size $2x$ in $2\times 50\times 16$ days

$y$ labourers Pond size $=2x$ in $20$ days

$y=50\times 2\times \frac{16}{20}=80$ labourers.