Let us say Amelia has y number of quarters and x number of nickel coins.
So total she has 15 coins.
[tex] x+y=15 [/tex]
[tex] x=15-y [/tex].................(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,
[tex] 0.05x + 0.25y =2.15 [/tex].................. (2)
Plugging x from (1) in (2)
[tex] 0.05(15-y) + 0.25y =2.15 [/tex]
On solving we get ,
y=7
x=15-y =15-7 = 8
Answer: There are 8 nickels and 7 quarters.
