Question

Suppose you have 20 coins that total $3.00. Some coins are nickels and some are quarters. Which of the following pairs of equations would you use to find out how many of each coin you have?

Answer 1

Explanation:

n + q = 20

.05n + .25q = 3.00

5n + 25q = 300

n + q = 20

5n + 25q = 300

-5n - 5q = -100

20q = 200

q = 10 quarters

n + 10 = 20

n = 10 nickels

(10 nickels, 10 quarters)