A person does his job in 30 days , the other in 20 days, how many days they consume if they work together Mcqs

A person does his job in 30 days , the other in 20 days, how many days they consume if they work together

(A) 10

(B) 12

(C) 15

(D) 13

Source: This question is taken from the PROVINCIAL MANAGEMENT SERVICE, ETC. BS-17