Question

A works twice as fast as B. If both of them can together finish a piece of work in 12 days, then B alone can do it in

(a) 24 days

(b) 27 days

(c) 36 days

(d) 48 days

Answer 1

Let B's 1 day's work =x

Then A's 1 day's work =2x

A and B's 1 day's work $=\frac{1}{12}$

$\therefore x+2x=\frac{1}{12}\Rightarrow 3x=\frac{1}{12}$

$\Rightarrow x=\frac{1}{12\times 3}=\frac{1}{36}$

$\therefore$ B can do the work in 36 days