Ramesh can finish a job in 20 days. He worked for 10 days alone and completed the remaining job working with Dinesh, in 2 days. How many days would both Dinesh and Ramesh together can complete the whole work?

Correct Answer: 4

Explanation:

Ramesh alone finish 1/2of the work in 10 days.
Remaining 1/2 of the job was finished by Ramesh and Dinesh together in 2 days.
Therefore, they both together can finish the complete job in 4 days.