45 men working 8 hours per day dig 40 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 answer:
A) 10 B) 20 C) 30 D) 40 E) 50
(45 * 8)/40 = (x * 6)/50 =&gt; x =75   75 – 45 =30   ANSWER:30
<result>C</result>
45 men working 8 hours per day dig 40 m deep. How many extra men should be put to dig to a depth of 50 m working 6 hours per day?