# Money Is a Special Decimal

Some rules will change a bit when you start learning about multiplication, but for addition and subtraction, money is really easy. All money is a decimal value with two places. You will see examples including $1.25, $65.98, and $26.34. No matter how big the value gets, you can only have two decimal places. One cent is 0.01. You can't give someone less than one cent if you hand them**bills**and

**coins**.

There are values less than a cent when you start figuring out

**tax**or

**interest**. But when you look at the money in your pocket, one penny is the smallest amount. We have a numbers tutorial if you want to learn more about decimals and money.

# Bring on Some Addition

Let's try one example. You know about adding harder decimals than these, so it shouldn't be a problem.**Question:**

Timmy runs down the street to buy some fruit. He picks out two apples that cost forty-five cents each and 3 oranges that cost eighty cents each. How much does he pay in total?

**Steps to Solve:**

0.45+0.45+0.80+0.80+0.80=?

We can group them and solve.

(.45+.45) + (.8+.8+.8) = .9 + 2.4 = 3.3

**Answer:**

Timmy owes $3.30 for his fruit.

Remember that even though our decimal answer didn't have a zero on the end, when you write out values for money, you always need two places to the right of the decimal point. You can't write that something costs $16.7 dollars. You should write $16.70 so people understand what you mean. Let's do one more...

**Question:**

Helen was having a party for three friends. One wanted a cupcake for $2.55, one wanted a hot dog for $1.20, and one wanted a piece of pizza for $1.25. How much did Helen pay for lunch?

**Steps to Solve:**

2.55+1.20+1.25=?

Let's look at this one in a stacked layout.

2.55 1.20 + 1.25? |

• You'll need to carry a little, but it's an easy problem with an answer of 5.00.

**Answer:**

Helen paid $5.00 for lunch.

If this were a science experiment and those were values of

**data**or measurements of weight, you might write down 5.0. The two decimal places are very important for money. If you have a bunch of zeros at the end of your number in science, you don't have to write them all.

## Related Activities

Add Coins with Values Less Than One Dollar
- Play Activity |
"Do You Have Enough Money?"More or Less?"Do You Have Enough Money?" - Values Less Than Thirty Cents
- Play Activity |

- Overview
- Number Types
- Factors
- Fractions
- Decimals
- Percentages
- Estimation
- Ratios
**Money**- Activities
- More Maths Topics

# Useful Reference Materials

**Wikipedia:**

*https://en.wikipedia.org/wiki/Fraction_%28mathematics%29*

**Encyclopædia Britannica:**

*http://www.britannica.com/topic/fraction*

**University of Delaware:**

*https://sites.google.com/a/udel.edu/fractions/*