Question 674377
15p + 7c = 55.40
12p + 10c = 61.70
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Multiply the first equation by 10 and the second by -7
10(15p+7c=55.40)
-7(12p+10c=61.70)
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150p + 70c = 554
-84p - 70c = -431.90
Add the equations to solve for p
150p + -84p + 70c + -70c = 554 + -431.90
66p = 122.10
{{{highlight_green(p = 1.85)}}} cost of paper clips
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15(1.85) + 7c = 55.40
27.75 + 7c = 55.40
7c = 55.40 - 27.75
7c = 27.65
{{{highlight_green(c = 3.95)}}} cost of index cards
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