Multiple choice

A contractor estimates that $3$ persons could rewire Jasminders house in $4$ days. If he uses $4$ persons instead of three, how long should they take to complete the job?

  1. $8$ days
  2. $3$ days
  3. $4$ days
  4. $9$ days
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This is an inverse proportion problem. 3 persons * 4 days = 12 man-days of work required. If 4 persons are used, the time taken is 12 man-days / 4 persons = 3 days.

AI explanation

Using the formula for inverse proportionality, the total work is 3 persons multiplied by 4 days, which gives 12 man-days. For 4 persons to complete the same job, the days required will be 12 man-days divided by 4 persons, resulting in 3 days.