Cans of soup

1
2
3
4

Number of servings
4
8
12
16

Write a function rule

N = 4C

C = 1
N = 4 * 1 =4

C = 2
N = 4 * 2 = 8

C = 3
N = 4 * 3 = 12

C = 4
N = 4 * 4 = 16