Question

The table shows the amount of lemon juice needed to make lemonade. (Unit 9 Lesson 3) Lemon juice (cups) 5 10 20 Servings 35 70 140 Are the two quantities proportional? If so, what is the constant of proportionality?

Answer 1

Lemon Juice (cups)    5    10    20
Servings                   35     70  140

The two quantities are proportional. Lemon Juice (cups) is the x-value ; while servings is the y-value.

  35 ÷   5 = 7
  70 ÷ 10 = 7
140 ÷ 20 = 7

The constant of proportionality is 7.

The equation would be: y = 7x