Question

for every 3 packages that marcella wraps, she uses \\( \frac { 1 } { 2 } \\) of a roll of wra
if she uses \\( 2 \frac { 1 } { 2 } \\) rolls of wrapping paper, how many packages has she
enter your answer in the box.

Explanation:

Step1: Find out how many times \(\frac{1}{2}\) is in \(2\frac{1}{2}\)

First, convert \(2\frac{1}{2}\) to an improper fraction: \(2\frac{1}{2}=\frac{2\times2 + 1}{2}=\frac{5}{2}\).
Then, calculate \(\frac{5}{2}\div\frac{1}{2}\). According to the division rule of fractions \(\frac{a}{b}\div\frac{c}{d}=\frac{a}{b}\times\frac{d}{c}\), so \(\frac{5}{2}\div\frac{1}{2}=\frac{5}{2}\times\frac{2}{1}=5\).

Step2: Calculate the number of packages

Since for every \(\frac{1}{2}\) roll, she wraps 3 packages. And we found that \(2\frac{1}{2}\) rolls contain 5 groups of \(\frac{1}{2}\) roll.
Multiply the number of groups by the number of packages per group: \(5\times3 = 15\).

Answer:

\(15\)