A) 80 days
B) 100 days
C) 110 days
D) 120 days
Correct Answer: D
Solution :
Work done by \[(A+B)\] in 1 day \[=\frac{1}{72}\] Work done by \[(B+C)\] in 1 day \[=\frac{1}{120}\] Work done by \[(C+A)\] in 1 day \[=\frac{1}{90}\] Work done by \[(A+B+C)\] n 1 day \[=\frac{1}{2}\,\left( \frac{1}{72}+\frac{1}{120}+\frac{1}{90} \right)\] \[=\frac{1}{2}\,\left( \frac{5+3+4}{360} \right)=\frac{1}{60}\] Work done by A in 1 day \[=\frac{1}{60}-\frac{1}{120}=\frac{1}{120}\] So, A alone will do in 120 days.
You need to login to perform this action.
You will be redirected in
3 sec
