Question

You have a total of 21 coins that are nickels and quarters. The coins have a value of $2.25. How many quarters do you have?

Answer 1

Explanation:

Let n represent the quantity of nickels and q represent the quantity of quarters, then set up a system of equations and solve for q.

Quantity: x + y = 21 → -5(x + y = 21) → -5x -5y = -105

Value: 5nx+ 25y = 225 → 1(5x + 25y = 225) → 5x + 25y = 225

20y = 120

y = 6

Answer 2

Answer: 6

Explanation:

Let n represent the quantity of nickels and q represent the quantity of quarters, then set up a system of equations and solve for q.

Quantity: n + q = 21 → -5(n + q = 21) → -5n -5q = -105

Value: 5n + 25q = 225 → 1(5n + 25q = 225) → 5n + 25q = 225

20q = 120

q = 6