Bella bought b boxes of cookies to bring to a party. Each box contains 18 cookies. She decides to keep two boxes. She brings 90 cookies to the party. How many boxes of cookies did Bella buy?

Question

Using b for boxes, determine the correct equation and the unknown number in this situation.

(1 point)
Responses

18b−2=90; b=5
18b−2=90; b=5

2b−18=90; b=54
2b−18=90; b=54

18b−36=90; b=7
18b−36=90; b=7

18b−36=90; b=6

Answer 1

To find how many boxes of cookies Bella bought, we can set up the equation based on the information given.

1. Each box contains 18 cookies.
2. Bella keeps 2 boxes, which means she brings the cookies from the remaining boxes to the party.
3. So, if she bought \( b \) boxes, she keeps 2 boxes, meaning she brings \( b - 2 \) boxes to the party.
4. The number of cookies she brings to the party can then be calculated as: \( 18(b - 2) \).
5. It is given that she brings 90 cookies to the party.

Now we can set up the equation:

\[ 18(b - 2) = 90 \]

Now, solving for \( b \):

1. Distribute the 18:
   \[ 18b - 36 = 90 \]

2. Add 36 to both sides:
   \[ 18b = 126 \]

3. Divide by 18:
   \[ b = 7 \]

Thus, the correct equation is:

\[ 18b - 36 = 90; \quad b = 7 \]

The answer is: 18b−36=90; b=7.