Question

a and b can complete a work in 15 days and 10 days respectively,in how many days they can finish it together

Answer 1

Step-by-step explanation:

A=15 days

1 day's work of a = 1/15

B=10 days

1 day's work of b = 1/10

Total work done by a and b in a day = 1/15 + 1/10

                                                            = 2+3/30

                                                            = 5/30

Number of days to do work = 1/(1day's work)

                                              = 1/(5/30)

                                              = 30/5

                                              = 6 days