Question

If $20$ people can build a wall in $7$ days, then the number of persons required to complete the work in $35$ days is:

• A. $4$
• B. $8$
• C. $12$
• D. $20$

Answer 1

The correct option is A $4$

The number of people working and length of the wall are in inverse proportion.

Work done by $20$ people in $7$ days=$20\times 7$
Let,the number of people required to complete the same work in $35$ days be $x$
Now,
$20\times 7=35x$
$=>\frac{140}{35}=x$
$=>x=4$