Question

Molly shared a spool of ribbon with 12 people. Each person received 3 feet of ribbon. Which equation can she use to find r, the number of feet of ribbon that her spool originally had?
3 + r = 12
r minus 3 = 12
3 r = 12
StartFraction r Over 12 EndFraction = 3

Answer 1

To determine the equation that Molly can use to find \( r \), the total number of feet of ribbon she had originally, let's analyze the situation.

Molly shared the ribbon with 12 people, and each person received 3 feet of ribbon. To find the total amount of ribbon \( r \), we need to calculate how much ribbon was distributed to all 12 people.

The total length of ribbon given to 12 people is:
\[
12 \text{ people} \times 3 \text{ feet/person} = 36 \text{ feet}
\]

So, we can represent this with the equation:
\[
r = 36
\]

However, none of the provided options directly represent this. Let's examine the options:

1. \( 3 + r = 12 \) - This does not make sense with the context.
2. \( r - 3 = 12 \) - This also does not fit the situation.
3. \( 3r = 12 \) - This incorrectly implies that there were 12 feet of ribbon total distributed among 3 people.
4. \(\frac{r}{12} = 3\) - This equation correctly expresses that if each of the 12 people received 3 feet, \( r \) (the total amount of ribbon) is 12 times 3.

Thus, the correct equation Molly can use is:
\[
\frac{r}{12} = 3
\]

This equation correctly correlates the total ribbon with the number of people and the amount each received.