If 4 men working 10 hours a day earn Rs. 800 per week, then 9 men working 6 hours a day will earn how much per week?	Choose the correct choice from the following choices:
A) rs 840	B) rs 1320	C) rs 1080	D) rs 1680	E) none of these

Rationale: "explanation : ( men 4 : 9 ) : ( hrs / day 10 : 6 ) : : 800 : x hence 4 * 10 * x = 9 * 6 * 800 or x = 9 * 6 * 800 / 4 * 10 = 1080 answer : c"
Answer: C