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Joanna went school supply shopping. She spent $23.25 on notebooks and pencils. Notebooks cost $2.49 each and pencils cost $1.08 each. She bought a total of 15 notebooks and pencils. How many of each did she buy?

User Sjoseph
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1 Answer

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Answer: 10 pencils and 5 notebooks.

Explanation:

We will create a system of equations using the information given. Let n be equal to the number of notebooks and p be equal to the number of pencils.

She spent $23.25 on notebooks and pencils. Notebooks cost $2.49 each and pencils cost $1.08 each.

$2.49n + $1.08p = $23.25

She bought a total of 15 notebooks and pencils.

n + p = 15

Next, we will solve for p by substituting.

n + p = 15 ➜ n = 15 - p

$2.49n + $1.08p = $23.25

$2.49(15 - p) + $1.08p = $23.25

$37.35 - $2.49p + $1.08p = $23.25

$37.35 - $1.41p = $23.25

-$1.41p = -$14.10

p = 10 pencils

Lastly, we will solve for n by substituting:

n = 15 - p

n = 15 - 10

n = 5

User Manofsins
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