Question

8 men or 12 boys can do a piece of work in 25 days. In how many days can 6 men and 11 boys do it?

Answer 1

let work dome by 1men in 1 day=1/x
and work done by 1 boy in 1 day=1/y
work done by 8men and 12 boys together in 25 days=25(8/x+12/y)
similarly,second eq =6/x+11/y
ATQ
8/x+12/y=1/25. 6/x+11/y=1
hope now you can solve it...
plz mark as brainlist

Answer 2

Let the Work to be Done be : W

Given : 8 Men can do a Piece of Work in 25 Days

⇒ One Man can do a Work of $\bf{: (\frac{W}{25 \times 8})}$ in One Day

⇒ Six Men can do a Work of $\bf{: (\frac{6W}{25 \times 8})}$ in One Day

Given : 12 Boys can do the Piece of Work in 25 Days

⇒ One Boy can do a Work of $\bf{: (\frac{W}{25 \times 12})}$ in One Day

⇒ 11 Boys can do a Work of $\bf{: (\frac{11W}{25 \times 12})}$ in One Day

⇒ The Work Done by 6 Men and 11 Boys in One Day :

$\bf{\implies (\frac{6W}{25 \times 8}) + (\frac{11W}{25 \times 12})}$

$\bf{\implies (\frac{1}{25})[(\frac{6W}{8}) + (\frac{11W}{12})]}$

$\bf{\implies (\frac{1}{25})(\frac{18W + 22W}{24})}$

$\bf{\implies (\frac{1}{25})(\frac{40W}{24})}$

$\bf{\implies (\frac{W}{15})}$

⇒ 6 Men and 11 Boys can Complete the Work in 15 Days