Question

A can do a job in 12 days and B can di the same job in 15 days. if both of them work togeather,how much time will they take to finish the job ?​

Answer 1

Step-by-step explanation:

A can do total work alone in 12 days.

so, In 1 day, A can do part of work = 1/12 of total.

Similarly,

B can do total work alone in 15days.

so, In 1 day, B can do part of work = 1/15 of total

According to the given question, A and B are doing the work together,

so, the time taken to complete the work together ===>

(let's find the part work done by them in 1 day)

so,

we have to add their work done by them in 1 day

therefore,

1/12 + 1/15

= 5 + 4

60

= 9/60

= 3/20 part of total.

hence, if they can work 3/20 part in 1 day then after dividing it by 1, we can find that how much time thay take to complete total work.

Therefore ,

after dividing it by 1 then it value get reciprocal ,

so,

the time taken by both of them by doing the work together => 20/3 days