Question

a can finish a work in 18 days and b can do the same work in 15 days. b worked for 10 days and left the job. in how many days a alone can finish the remaining work? a) 7 b) 6 c) 5 d) 10

Answer 1

b worked for 10 days. So, remaining 5 days work is pending. This is 5/15 = 1/3rd of work.

a can finish the work in 18 days. So, 1/3rd of work can be done in 18 × 1/3 = 6 days.

Option: (b)

Answer 2

Answer:

The correct option is b) 6 days.

Step-by-step explanation:

Consider the provided statement.

A can finish a work in 18 days and B can do the same work in 15 days.

The LCM of 18, and 15 is:

18 = 3×3×2

15 = 5×3

LCM = 3×3×2×5 = 90 Unit

Now efficiency of A is 90/18 = 5 units per day.

The efficiency of B is 90/15 = 6 units per day.

B work for 10 days, thus.

10×6 = 60 units

That means the remaining work is 90-60 = 30 units.

Now, find the 30 units of work done by A:

30/5 = 6 days

Hence, the correct option is b) 6 days.