SOLUTION: Molly has a collection of coins worth $5.20. She has 8 more nickles than quarters. How many nickels and quarters does Molly have? I keep getting decimals for my answers. This is w

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Molly has a collection of coins worth $5.20. She has 8 more nickles than quarters. How many nickels and quarters does Molly have? I keep getting decimals for my answers. This is w      Log On


   



Question 695715: Molly has a collection of coins worth $5.20. She has 8 more nickles than quarters. How many nickels and quarters does Molly have?
I keep getting decimals for my answers. This is what I got 1.88 quarters and 9.88 nickles.
my equations that I am using are 5.20=.05n+ .25q and my other equation is n=q+8. I need to solve this using system of equations. Can you help me figure out what I did wrong.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +n+ = number of nickels she has
Let +q+ = number of quarters she has
given:
(1) +n+=+q+%2B+8+
(2) +5n+%2B+25q+=+520+ ( in cents )
------------------------------
Substitute (1) into (2)
(2) +5%2A%28+q+%2B+8+%29+%2B+25q+=+520+
(2) +5q+%2B+40+%2B+25q+=+520+
(2) +30q+=+480+
(2) +q+=+48%2F3+
(2) +q+=+16+
and, since
(1) +n+=+q+%2B+8+
(1) +n+=+16+%2B+8+
(1) +n+=+24+
She has 24 nickels and 16 quarters
You made some minor mistake
check answer:
(2) +5%2A24+%2B+25%2A16+=+520+
(2) +120+%2B+400+=+520+
(20 +520+=+520+
OK