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murzikaleks [220]
3 years ago
13

Lucy was given $28.87 to buy 3 story books and 4 comic books. However she bought 4 storybooks and 3 comic books and had $2.69 le

ft. How much did each comic book cost?
Mathematics
1 answer:
vova2212 [387]3 years ago
8 0

Answer:

$5.27 each

Step-by-step explanation:

<em><u>EQUATION 1:</u></em>

--> Price of each story book: x

--> Quantity of story books: 3

--> Price of 3 story books: 3x

--> Price of each comic book: y

--> Quantity of comic books: 4

--> Price of 4 comic books: 4y

--> Total amount: $28.87

--> Equation----> 3x + 4y = 28.87

<u><em>EQUATION 2:</em></u>

--> Price of each story book: x

--> Quantity of story books: 4

--> Price of 3 story books: 4x

--> Price of each comic book: y

--> Quantity of comic books: 3

--> Price of 4 comic books: 3y

--> Total amount: $28.87 - 2.69 = $26.18

--> Equation----> 4x + 3y = 26.18

<em><u>SOLVE:</u></em>

3x + 4y = 28.87 <em>(Multiply by 4)</em>

4x + 3y = 26.18 <em>(Multiply by -3)</em>

--> 12x + 16y = 115.48

--> -12x - 9y = -78.54

<em>12x-12x will be cancelled.</em>

--> 16y-9y = 115.48-78.54

--> 7y = 36.94

--> y = 5.27

Therefore, each comic book cost $5.27.

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