A can do a work in 15 days B in 14 days and C in 16 days . If they work on it together then in how many days required to complete the work?  Select: A) 3360 / 210 B) 3360 / 21 C) 3360 / 674 D) 3360 / 240 E) 3360 / 224

Rationale: person ( a ) ( b ) ( c ) ( a + b + c ) time - ( 15 ) ( 14 ) ( 16 ) rate - ( 224 ) ( 240 ) ( 210 ) ( 674 ) work - ( 3360 ) ( 3360 ) ( 3360 ) ( 3360 ) therefore a + b + c requires ( 3360 / 674 ) days to complete entire work = 3360 / 674 answer is c
Answer: C