A) 120 days
B) 140 days
C) 150 days
D) 160 days
Correct Answer: B
Solution :
\[(A+B)'s\] 1 day's work \[=\frac{1}{84};(B+C)'s\] 1 day's work \[=\frac{1}{140};(A+C)'s\] 1 day's Work \[=\frac{1}{105}\] Adding, we get: 2(A+ B + C)'s 1 day's work \[=\frac{1}{84}+\frac{1}{140}+\frac{1}{105}=\frac{12}{420}=\frac{1}{35}\] \[(A+B+C)'s\] 1 day?s work \[=\frac{1}{70}\] So, A?s 1 day?s work \[=\frac{1}{70}-\frac{1}{140}=\frac{1}{140}\] A alone can do that work in 140 days.You need to login to perform this action.
You will be redirected in
3 sec