Question

In her science classroom Jane noticed that the lengths (in inches) and the weights (in ounces) of the class's pet snakes were directly related by the equation y = kx, where x is the length and y is the weight. Use the information in the table to find the weight of a snake that is 12 inches long.

A.25.0
B.27.5
C.30.0
D.32.5

Answer 1

30.0 ounces is correct. Using any pairs of numbers in the table,plug into values for x and y and solve for k.

Answer 2

Use one of the ordered pairs that are given to find the value of 'k', the CONSTANT of variation. This number will not change, hence the word 'constant'.
15 = k*6; dividing both sides by 6 we get k = 2.5; The equation used for the table is y = 2.5x
You can find any value now by using this formula.
y = 2.5*12
y = 30