Answer:
1. (a) a+b=86
2. (c) 5.99a+9.99b≤600
Explanation:
1.
a = amount of 16gb memory sticks
b = amount of 21gb memory sticks
Gary is buying a memory sticks for each of the 86 teachers. Therefore the total sum of both 16gb and 32gb memory sticks should equal 86:
a+b=86
2.
a = amount of 16gb memory sticks
b = amount of 21gb memory sticks
Each 16gb memory stick cost $5.99, and each 32gb one costs $9.99. Therefore...
5.99a = total cost of 16gb memory sticks
9.99b = total cost of 32gb memory sticks
Gary has to spent an amount less than or equal to $600. Therefore, the total sum of the costs of both 16gb and 32gb memory sticks should be less than or equal to 600:
5.99a+9.99b≤600