Question

A and B took a job to be completed in 20 days. They started working together and after 12 days, C joined them and the whole job finished in 15 days. How much time would C require to complete the job if only C was hired​

Answer 1

Answer:

Hope this will be helpful to you.

Answer 2

Step-by-step explanation:

let us take LCM of 20,12,15.....

LCM of 20, 12, 15 is 60....

let us assume that there are 60 choclates in a bowl and those choclates have to eat by the A, B and C....

according to ques......A and B together can eat those 60 choclates in 20 days....which means A and B can eat 3 choclates/day.......

now the question begins.....

A and B started eating the choclates and eated for 12 days according to the ques....

we know that A and B can eat 3 choclates/day.... hence they had eaten 12×3= 36 choclates in 12 days.....the remaining choclates are 60-36=24.......now c joined to them which means A+B+C completed those 24 choclates in 3 days ....but we know that A +B can eat 9 choclates in 3 days....so 24-9=15 choclates has eaten by C alone in 3 days.....

so we came to know that C alone can eat 5 choclates / day ( 15 choclates ÷ 3days = 5 choc / day)....now the ques is, In howmany days, C alone can eat those 60 choclates....

60÷5 = 12 days.....

so C alone can complete the entire work in 12 days....