Mathematics, Operations (+, -, x, /, etc.), Problem Solving

Grade 3- 5

Objective

Students use coin values to solve problems.

Directions

Introduce the lesson by showing students a variety of coins and coin combinations.

• Bertha Biggspender broke open her piggy bank.
• She had a total of seven coins worth $0.19.
• Which coins did she have?

To solve problems of this type, you need to know three things:

• the number of coins
• the total amount of money
• any kinds of coins not included

Pennies First
Always do the pennies first in these problems. To have $0.19, Bertha had to have at least 4 pennies because pennies are the only coins which could be used for the last four cents. This leaves $0.15 to be accounted for and three remaining coins. The only coins which will work for this combination of money are three nickels.
Make a Chart
Record the information on a chart like this:

Number of Coins	Amount of Money
4 pennies	$0.04
3 nickels	$0.15
Totals: 7 coins	$0.19

Challenging Problems
Bertha Biggspender found her wallet which had seven coins worth $0.91.
She did not have any dimes or half dollars. Which coins did she have?
Do the pennies first--she had to have at least one penny. There were not enough coins to have more than one penny. She has six coins which equal $0.90. She had no dimes and no half dollars so the combination must include only quarters and nickels. A total of three quarters and three nickels will work.

Number of Coins	Amount of Money
1 penny	$0.01
3 quarters	$0.75
3 nickels	$0.15
Totals: 7 coins	$0.91

Reminders

• Make a chart.
• Do pennies first.
• Do not forget half dollars.
• Match exact number of coins.
• Match exact amount of money.

Resources

• Piggy Bank Math activity pages
• pencils