Question

Sam has $2.25 in quarters and dimes, and the total number of coins is 12. How many quarters and how many dimes?

Answer 1

N₁*$0.10 + n₂*$0.25 = $2.25

n₁ + n₂ = 12

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This means that:

n₁ = 12 - n₂

And:

(12 - n₂)*$0.10 + n₂*$0.25 = $2.25

12*$0.10 - n₂*$0.10 + n₂*$0.25 = $2.25

$1.20 + n₂*$0.05*(5-2) = $2.25

$1.20 + n₂*$0.05*3 = $2.25

$1.20 + n₂*$0.15 = $2.25

n₂*$0.15 = $2.25 - $1.20

n₂*$0.15 = $1.05

n₂ = ($1.05)/($0.15)

n₂ = 7

If n₂ = 7:

n₁ + 7 = 12

Therefore, n₁ = 5.

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Answer:

5 dimes and 7 quarters.

Answer 2

The accurate answer would be 5 dimes and 7 quarters and if you add them up will equal 12 coins in total