30 men can complete a piece of work in 18 days. In how many days will 27 men complete the same work ?	Choose the most appropriate option
A) 20	B) 77	C) 36	D) 25	E) 13

Rationale: "explanation : less men , means more days { indirect proportion } let the number of days be x then , 27 : 30 : : 18 : x [ please pay attention , we have written 27 : 30 rather than 30 : 27 , in indirect proportion , if you get it then chain rule is clear to you : ) ] { \ color { blue } x = \ frac { 30 \ times 18 } { 27 } } x = 20 so 20 days will be required to get work done by 27 men . answer : a"
Answer: A