Answer:
See the attached worksheet.
Explanation:
The approach is to use the staffing ratios to calculate the numbher of staff required for each activity. Some of the results are fractions, so they are rounded up to the nearest whole number. The attached worksheet shows the distribution of the 17 staff among the activities.
Reducing the staff levels is best achioeved by moving children out of a class having the lowest Child/Staff ratio into one having the highest. Those two activities are Horse Riding (at 4:1 Kids/Staff) and Canoeing (at 10:1 Kids/Staff). If we move 6 kids for riding to canoing, the staff level requirement drops to 15, as noted. There are challeneges with rounding in this calculation, so one might debate the actual staffing needs.