Answer: 3 pieces of string.
Step-by-step explanation:
Given: Li needs 15 pieces of string each 1/2 inch long.
Thus, total string required by Li \(=15\times\frac{1}{2}\text{inch}=7.5\text{inches}\)
As she cut a 6-inch piece of string .
So the length of string she needs\(=7.5-6=1.5\)
Since, each piece of string has length 1/2 inch or 0.5 inch, then the number of pieces she need \(=\frac{1.5}{0.5}=3\)
Hence, she need 3 pieces of string.
