Question

A group of 10 workers can plough a field in 20 days. This group starts the work and after every 2 days, 2 additional workers join the group. The efficiency of each
worker is the same. On which day workers finish ploughing the field?​

Answer 1

Answer:

In just 2 days.

Step-by-step explanation:

Can't solve the problem so easy!!

Answer 2

Answer:

Step-by-step explanation:

it may be easier to use percentages to compute the amount of days. A single worker would need 200 days to complete the job, so the rate of a single worker is 1/200 = 0.5%.

The combined rate in the beginning would be 5% per day, and we add 1% every two days since we get 2 more workers every day.

Then we can start adding two days at a time until we reach 100%: 10% + 12% + 14% + 16% + 18% = 70%. Add another 20% and the next day of 11% to reach 100%.

In total that took 2*5 + 2 + 1 = 13 days.

Ans:  13