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10 months ago

Jennifer has 25 coins with a total value of $4.25. The coins are quarters and nickels. How many of each does she have?

Mathematics

1 answer:

kirill115 [55]10 months ago

8 0

Answer:

15 quarters, 10 nickels

Step-by-step explanation:

$q+n=25$

$0.25q+0.05n=4.25$

multiply the first equation by -0.25 and add the second equation to it

$-0.25q-0.25n=-6.25\\0.25q+0.05n=4.25$
________________
$-0.2n=-2$

$n=\frac{-2}{-0.2} =10$ has 10 nickels

$q=25-n=25-10=15$ has 15 quarters

10(.05) +15(0.25) = 0.5 + 3.75 = 4.25

Hope this helps

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