If 20 men can build a water fountain 56 metres long in 6 days, what length of a similar water fountain can be built by 35 men in 3 days? Choose the correct answer:	A) 40 m	B) 44 m	C) 47 m	D) 49 m	E) 50 m
Explanation :   Let the required length be x metres   More men, More length built (Direct Proportion)   Less days, Less length built (Direct Proportion)   Men 20: 35   Days 6: 3 : : 56 : x   Therefore (20 x 6 x x)=(35 x 3 x 56)   x=(35 x 3 x 56)/120=49   Hence, the required length is 49 m.   Answer : 49 m
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If 20 men can build a water fountain 56 metres long in 6 days, what length of a similar water fountain can be built by 35 men in 3 days?