A factory hired 9 workers and found that their average productivity per day was 42.75 units. Later, 3 more workers were hired. The average productivity of all 12 workers then became 45.5 units. However, one of the new 3 workers made 52.2 units daily, and another made 48.4 units daily. What is the daily productivity of the third new worker?
Show answer & explanation
Correct answer: B
Explanation
Given:
First workers = 9
Average productivity = 42.75
Total workers = 12
New average productivity = 45.5
Productivity of two new workers = 52.2 and 48.4
Total output of the first 9 workers = 9 × 42.75 = 384.75
Total output of the 12 workers = 12 × 45.5 = 546
Total output of the new 3 workers = 546 − 384.75 = 161.25
Productivity of the third worker = 161.25 − (52.2 + 48.4) = 60.65
Productivity of the third worker = 60.65 units