’A’ can complete a work in 20 days while B is 25% more efficient than ’A’. B worked for 6 days and left, remaining work is completed by ’C’ in 15 days. Find in how many days ’C’ can complete the whole work alone?

B can complete work alone in = 20× $frac{4}{5}$ = 16 days

Let C alone can complete work in ’x’ days

ATQ,

$frac{6}{{16}} + frac{{15}}{x} = 1$

$Rightarrow frac{{15}}{x} = frac{{10}}{{16}} Rightarrow x = frac{{15 imes 16}}{{10}} = 24$ $days$