Question

A man, a woman and a child can complete a job in 5, 6 and 30 days, respectively. How many boys must assist 1 man and 1 woman to complete the job in 1/6 of a day?

A. 13 B. 17 C. 23 D. 19 E. None of these​

Answer 1

$\huge\mathcal{\fcolorbox{cyan}{yellow} {{solution }}}$

If they have to complete the 30 units work in

$\frac{1}{6}$

Of the day.

So it means their combined efficiency should be 180 per day.

(1 man + 1 woman)'s efficiency

=> 5 + 6 = 11

Unit left = 180 - 11 = 169 units.

Now No. of childs required :~

$= > \frac{t.w}{eff. \: of \:a \: child} = \frac{169}{1}$

Answer - 169 boys.