(d) 41
1 man’s 1 days’ work = \(\frac{1}{3}\)
1 woman’s 1 days’ work = \(\frac{1}{4}\)
1 boy’s 1 days’ work = \(\frac{1}{12}\)
Let the number of boys to assist be x. Then
\(\frac{1}{3}\)+ \(\frac{1}{4}\)+ \(\frac{X}{12}\) = \(\frac{1}{\frac{1}{4}}\)
\(\Rightarrow\) \(\frac{4+3+X}{12}\) = 4
\(\Rightarrow\) 7 + x = 48
\(\Rightarrow\) x = 41 boys