Answer: 30
Explanation:
From the question, we are informed that Tina has 10 packages of yarn to knit a scarf and that he uses ⅓ package of yarn for each inch of length she adds to the scarf.
Since she used all the yarn, the length of the cloth would be:
= 10 ÷ 1/3
= 10 × 3
= 30 inch