Question

Sixty men can build a wall in
40 days, but though they begin the work together, 5 men quit every ten days. The time needed to build the wall is:
​

Answer 1

$\huge\underline\mathfrak{\pink{Solution }}$

Total man days = 2400

60 × 10 × 55 × 10 + 50 × 10 + 45 × 10

= 2100

man days

$\frac{300}{40} = 7.5 \: days$

Total days

= 10 + 10 + 10 + 10 + 7.5 = 47.5 days.

Answer 2

$\LARGE{\color{gold}{\textsf{\textbf{Answer:-}}}}$

Total man days = 2400

60 × 10 × 55 × 10 + 50 × 10 + 45 × 10

= 2100

man days

300/40 = 7.5 days

Total days

= 10 + 10 + 10 + 10 + 7.5 = 47.5 days.