Question

Lucy is knitting a blanket and needs to buy some more yarn. At her local craft store, 2 skeins of yarn cost $7 and 8 Skeins of yarn cost $28. Which equation represents this direct variation

Answer 1

7 / 2

Explanation:

Given that:

2 skeins of yarn = $7

7 α 2

7 = 2k

2k = $7

k = constant of proportionality

Make k the subject

Divide bith sides by 2

k = 7/2

To test the correctness of k

8 skeins cost $28

Thus,

8 * k should equal 28

8 * 7/2 = 56/2 = 28