A manufacturing operation began with 85 staff members. On April 1, 4 employees were hired; on June 1, 3 employees retired; and on November 1, another 3 employees were hired. Determine the average number of workers during the year.

A) 86.75
B) 88
C) 89.25
D) 91.25
E) 92.75

The average number of workers can be calculated by taking the weighted average based on the number of months each staffing level was maintained. Initially, there were 85 staff members. On April 1, 4 employees were hired, bringing the total to 89. This level was maintained for April and May (2 months). On June 1, 3 employees retired, reducing the staff to 86, which was maintained for June, July, August, September, and October (5 months). On November 1, another 3 employees were hired, increasing the staff to 89, which was maintained for November and December (2 months). The calculation is as follows:- 85 staff for 3 months (January, February, March): 85 * 3 = 255- 89 staff for 2 months (April, May): 89 * 2 = 178- 86 staff for 5 months (June, July, August, September, October): 86 * 5 = 430- 89 staff for 2 months (November, December): 89 * 2 = 178Total staff-months = 255 + 178 + 430 + 178 = 1041Average number of workers = Total staff-months / 12 months = 1041 / 12 = 86.75