Twenty four men can do a work in 42 days. How many men are required to complete the work in 21 days? Select.
A) 20  B) 10  C) 50  D) 40  E) 48
E   48   We have M1 D1 = M2 D2   So, 24 * 42 = M2 * 21 =&gt; M2 = 48.   Answer is 48
<result>E</result>
Twenty four men can do a work in 42 days. How many men are required to complete the work in 21 days?