30 men can finish a piece of work in 28 days. How many days will be taken by 21 men to finish.
More the no. of men, lesser the days. So, it is an inverse proportion.
Let the required time be x days.
⇒ 30 × 28 = 21 × x
⇒ x = 
= 40 days
5
30 men can finish a piece of work in 28 days. How many days will be taken by 21 men to finish.
More the no. of men, lesser the days. So, it is an inverse proportion.
Let the required time be x days.
⇒ 30 × 28 = 21 × x
⇒ x = = 40 days