A and B can do a piece of work in 4 days. With the help of C they finish the work in 3 days. C alone can do that piece of work in? Choices
A) 4 DAYS	B) 21 DAYS	C) 13 DAYS	D) 12 DAYS	E) 3 DAYS
C = 1/3 – 1/4 = 1/12 =&gt; 12 days   Answer:12 DAYS
<result>D</result>
A and B can do a piece of work in 4 days. With the help of C they finish the work in 3 days. C alone can do that piece of work in?