Question

CRITICAL THINKING A local zoo employs 36 people to take care of the animals each day. At most, 24 of the employees work full time. Write and solve an inequality that represents the fraction of employees who work part-time. Please Explain how you got your answer.

Answer 1

We assume all employees are either full-time or part-time.

36 = 24 + 12

If the number of full-time employees is 24 or less, the number of part-time employees must be 12 or more. (Thinking, based on knowledge of sums.)

_____

You can write the inequality in two stages.

1. First, write and solve an equation for the number of full-time employees in terms of the number of part-time employees.
2. Then apply the given constraint on full-time employees. This gives an inequality you can solve for the number of part-time employees.

Let f and p represent the numbers of full-time and part-time employees, respectively.

... f + p = 36 . . . . . . given

... f = 36 - p . . . . . . . subtract p. This is our expression for f in terms of p.

... f ≤ 24 . . . . . . . . . given

... (36 -p) ≤ 24 . . . . substitute for f. Here's your inequality in p.

... 36 - 24 ≤ p . . . . add p-24

... p ≥ 12 . . . . . . . . the solution to the inequality