Question

Kevin and Randy Muise have a jar containing 80 ​coins, all of which are either quarters or nickels. The total value of the coins in the jar is ​$11.80. How many of each type of coin do they​ have?

Answer 1

Answer:

• 39 quarters and 41 nickels

Step-by-step explanation:

Let the number of quarters be x and nickels be y.

Given:

• Quarter is 25 cents
• Nickel is 5 cents
• Number of coins is 80
• Total amount is $11.80 = 1180 cents

We have equations:

• x + y = 80
• 25x + 5y = 1180

Solve the system by elimination, subtract 5 times the first equation from the second one:

• 25x + 5y - 5x - 5y = 1180 - 80*5
• 20x = 780
• x = 780/20
• x = 39

Find the value of y:

• 39 + y = 80
• y = 80 - 39y = 41

Verify:

• 25*39 + 5*41 = 975 + 205 = 1180