Irene R. answered 07/23/20
BS in Mechanical Engineering and Certified math teacher for 13 years
Hi Jessica,
Let's use the variable, n , to represent the NUMBER of nickels and the variable, q , to represent the NUMBER of quarters.
Since there is a total of 39 coins, we can write the following equation:
n + q = 39
Because each nickel is worth 5 cents and each quarter is worth 25 cents, we can write the following equation:
5n + 25q = 595
Now we can solve these two equations with two unknowns (using elimination):
n + q = 39
5n + 25q = 595
Multiply the first equation by -5 so that we can solve for q:
n + q = 39 becomes -5n - 5q = -195
Now combine this new equation with the second one:
-5n - 5q = -195
5n + 25q = 595
20q = 400
q = 20
There will be 20 quarters.
Since there is a total of 39 coins, there will be 19 nickels.
The value of these coins is indeed $5.95:
20 • $0.25 + 19 • $0.05 = $5 + 0.95 = $5.95
Ranee M.
Hello! Thank You greatly for taking the time to explain this step by step. I was struggling and my teacher was no help at all. With the example you provided, I can now understand how to solve the problem. Again, Thank You!09/05/22