If 6 men and 8 boys can do a piece of work in 10 days while 26 men and 48 boys can do the same in 2 days, the time taken by 15 men and 20 boys in doing the same type of work will be:
4 days
5 days
6 days
7 days
Explanation:
Let 1 mans 1 days work = $ x $ and 1 boys 1 days work = $ y $.
Then, 6$ x $ + 8$ y $ =$ \dfrac{1}{10} $and 26$ x $ + 48$ y $ =$ \dfrac{1}{2} $.
Solving these two equations, we get : $ x $ =$ \dfrac{1}{100} $and $ y $ =$ \dfrac{1}{200} $.
[15 men + 20 boy]s 1 days work =$ \left(\dfrac{15}{100} +\dfrac{20}{200} \right) $=$ \dfrac{1}{4} $.
$\therefore$ 15 men and 20 boys can do the work in 4 days.