A is thrice as efficient as B and is, therefore, able to finish a piece of work 10 days earlier than B. In how many days A and B will finish it together?  Choose one:
A) 14 days  B) 5 days  C) 8 days  D) 4 days  E) 3 days
WC = 3:1   WT = 1:3   x 3x   1/x – 1/3x = 1/8   x = 16/3   3/16 + 1/16 = 1/4 =&gt; 4 days   ANSWER:4 days
<result>D</result>
A is thrice as efficient as B and is, therefore, able to finish a piece of work 10 days earlier than B. In how many days A and B will finish it together?