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3 years ago

Miguel has a total of 27 dimes and nickels. The total value of the coins is $1.80. How many dimes and nickels does he have?

Mathematics

1 answer:

soldi70 [24.7K]3 years ago

5 0

Answer:

There are 9 dimes and 18 nickels.

Step-by-step explanation:

Let d = be the number of dimes

n = be the number of nickels

d + n = 27...eq.1

0.10d + 0.05n = 1.80...eq.2

Solve the system of equations

d + n = 27

10d + 5n = 180 ( multiply eq.2 by 100 )

-5d - 5n = -135

5d = 45

d = 9 , there are 9 dimes so,0.90

n = 27 - 9 = 18, there are 18 nickels so, 0.90

To check: 9 dimes + 18 nickels = 27 coins

0.90 + 0.90 = $ 1.80 total value of the coins

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