A) 80 days
B) 104 days
C) 52 days
D) 68 days
Correct Answer: B
Solution :
Rate of digging = 8 : 5 \[\therefore \] Man complete the work in = 5x days and boy complete the work in = 8x days \[\therefore \] \[\frac{1}{5x}+\frac{1}{8x}=\frac{1}{40}\] \[\Rightarrow \] \[\frac{8+5}{40x}=\frac{1}{40}\] \[\Rightarrow \] \[\,x=13\] \[\therefore \] Boy takes the time to complete the work alone \[=8x=8\times 13=104\]daysYou need to login to perform this action.
You will be redirected in
3 sec