18 men working 8 hours per day dig 30 m deep. How many extra men should be put to dig to a depth of 50 m working 6 hours per day?	Choose the correct choice
A) 22  B) 66  C) 88  D) 100  E) 281

Rationale: "( 18 * 8 ) / 30 = ( x * 6 ) / 50 = > x = 40 40 – 18 = 22 answer : a"
Answer: A