63 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?
Pick one:
A) 87
B) 77
C) 66
D) 55
E) 97

Rationale: "( 63 * 8 ) / 30 = ( x * 6 ) / 50 = > x = 140 140 – 63 = 77 answer : b"
Answer: B