Doris uses 8 square pieces of fabric to make one scarf. Each side of a square piece of fabric is 1/4 foot in length. Doris can buy large pieces of fabric that are 1/4 foot long and 2 feet wide. How many large pieces of fabric should she buy to make 7 scarves?

7 pieces

Step-by-step explanation:

Given that,

length of square pieces of fabric = 1/4 foot

Doris used 8 of these piece so total fabric used

8 (l²)

= 1/2 foot²

1 scarf area = 1/2 foot²

7 scarf area = 7 * 1/2 foot²

= 7/2 foot²

When Doris uses piece of fabric that is 1/4 by 2 foot

area of one piece of that fabric = 2 * 1/4

= 2/4

= 1/2foot²

So,

number of pieces required to make 7 scarfs = (7/2) / (1/2)

= 7 pieces