Question

A,b,c worked individually 25,30,50,a started the working after 5 days b joined,after 3 days c joined ..how many days required to complete ..shortcut

Answer 1

A can finish the work in 25 days

⇒ 1 day = 1/25 of the work

B can finish the work in 30 days

⇒ 1 day = 1/30 of the work

C can finish the work in 50 days

⇒ 1 day = 1/50 of the work

.

A worked for first 5 days alone

1/25 x 3 = 3/25 of the work work completed..

.

A and B worked for the next 3 days

3 x (1/25 + 1/30 ) = 11/50 of the work work completed.

.

Amount of work left:

1 - 3/25 - 11/50 = 33/50

.

Amount of work A, B and C can do in a day:

1/25 + 1/30 + 1/50 = 7/75

.

Find the number of days needed:

Number of days needed: 33/50 ÷ 7/75 = 7 days

.

Find the total number of days needed:

Total number of days needed altogether = 5 + 3 + 7 = 15 days