Question

amelia has 2.15 in coins. all of her coins are either quarters or nickels and she has 15 coins in her pile. how many of each coin does she have?

Answer 1

Let us say Amelia has y number of quarters and x number of nickel coins.

So total she has 15 coins.

`x+y=15`

`x=15-y`.................(1)

Now she has total amount = $2.15

1 dollar = 20 nickels and 1 dollar = 4 quarters

1 nickel = 0.05 dollar and 1 quarter = 0.25 dollar

so we can say that in terms of dollars,

`0.05x + 0.25y =2.15`.................. (2)

Plugging x from (1) in (2)

`0.05(15-y) + 0.25y =2.15`

On solving we get ,

y=7

x=15-y =15-7 = 8

Answer: There are 8 nickels and 7 quarters.