Question

2. A cup of coffee costs $2. If the total cost

IS $18, how many cups of coffee were purchased?
a. Write an equation:
b. What is the constant of proportionality?

Answer 1

The equation is c=2n

The constant of proportionality is 2

$18 will buy 9 cups of coffee

Explanation:

Cost c=2*n

where c is the number of cups

The constant of proportion is 2

If cost is $18, then

18 = 2n

n = 18/2

n = 9

$18 will purchase 9 cups of coffee