Alex has 84 quarters and nickels worth a total of $17.80.

1 answer:

6 0

The equation which can be used to find the number of quarters and nickels is; n + q = 84, 0.05n + 0.25q = 17.80.

<h3>Quarters and nickels</h3>

Total coins = 84
Total value = $17.80

let

Number of quarters = q
Number of nickels = n

n + q = 84

0.05n + 0.25q = 17.80

From equation (1)

n = 84 - q

Substitute into (2)

0.05n + 0.25q = 17.80

0.05(84 - q) + 0.25q = 17.80

4.2 - 0.05q + 0.25q = 17.80

- 0.05q + 0.25q = 17.80 - 4.2

0.20q = 13.60

q = 13.60 / 0.20

q = 68

Substitute q = 68 into

n + q = 84

n + 68 = 84

n = 84 - 68

n = 16

Therefore, the number of quarters and nickels are 68 and 16 respectively.

Learn more about quarters and nickels:

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