Question

A small store sells Cds and DVDs. The Cds sell for $9 each. The DVDs sell for $11 dollars each. Cody is working part time and sells a totalof $204 worth of CDs and DVDs during his shift. He knows 20 items were sold. How many Cds did hrle sell

Answer 1

Answer:

He sells 8 CDs and 12 DVDs.

Step-by-step explanation:

In order to solve this, we have to set up a system of equations. We'll let x equal the amount of CDs and y equal the amount of DVDs. First, we'll set up an equation for the total number of items sold.

CDs + DVDs = 20 items

x + y = 20

Now we can set up one for amount of money made.

$9 for every CD + $11 for every DVD = $204

9x + 11y = 204.

Now that we have 2 equations we can solve. To do so, we'll multiply the first equation by -9 and then add them together.

-9x - 9y = -180

9x + 11y = 204

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2y = 24

y = 12

Now that we have the y value, we can find the x value by plugging into either equation.

x + y = 20

x + 12 = 20

x = 8