Question

A and b can do a job in 6 and 12 days respectively. They began the work together but a leaves after 3 days. Then the total number of days needed for the completion of the work is :

Answer 1

a takes 6 days for completion of the work and B takes 12 days for completion of the work it means they both will take 18 days to completion of the work but a leaves that work before 3 days of finishing this work it means Bee takes double of its it means b will take 6 days more to completion of the work it means a works 3 days and B will works 18 days to completion of this work so your answer is 18 + 3 is equal to 21