Question

A team of seven workers started a job, which can be done in 11 days. On the morning of the fourth day, several people left the team. The rest of the team finished the job in 14 days. How many people left the team?

Let x be the number of people who left the team.
(Hint: Focus on the work left after several workers left. )

Answer 1

• 3 people left

Explanation:

• The job can be completed by 7 people in 11 days
• The job is equivalent of 7*11 = 77 people*days

After 3 days, job left:

• (11 - 3)*7 = 56 people*days

This was completed by 7 - x people as x people left

Time needed was 14 days, we have new equation:

• 14(7 - x) = 56
• 7 - x = 4
• x = 7 - 4
• x = 3

As we found, 3 people left