Aperson x can clean up all of the crime in a city in 10 hr working alone. person y can do the same job alone in 12 hr. if person y starts crime fighting at 9 a. m. and person x joins him at 10 a. m., at what time will they have all the crime cleaned up?

They will clean up all the crime at PM.

Step-by-step explanation:

clean up all crime in .

The work done by is

cleanup all crime in

The work done by in

starts at and starts at .

let after hours from they will finish the work.

worked for and worked for

Multiply both side by

Hence they will finish work ofter

They both will finish work at

i think it is d. hope this