 # Banknotes of the United States Dollar

Banknotes, or bills, are the other form of currency we use. Bills have a greater value than coins, so they are often used for larger amounts of money. The different bills are the \$$1$ bill, \$$2$ bill, \$$5$ bill, \$$10$ bill, \$$20$ bill, \$$50$ bill and \$$100$ bill. Of these, the \$$2$ bill is the rarest, and very seldom used, so we won’t use it in the examples below. In the figure below you can see the relationships between some of the different bills: You can also collect enough coins so that they have the same value as some of the bills, like in the figure below. Now we are going to look at some examples where we use bills to buy things.

Example 1

A basketball costs $\text{}\text{}15\text{}$. Which bills could you use to buy one?

 $15=10+5$

You can use a \$$5$ bill and a \$$10$ bill.

Example 2

A box of LEGO costs $\text{}\text{}5\text{}$. You pay with a $\text{}\text{}10\text{}$ bill. What is your change?

 $\text{}10˘\text{}5=\text{}5$

Your change is a \$$5$ bill.

Example 3

A PlayStation game costs $\text{}\text{}65\text{}.$ What bills could you use to buy the game?

 $\text{}65=\text{}50+\text{}10+\text{}5$

You can use a \$$50$ bill, a \$$10$ bill and a \$$5$ bill.

Example 4

A scooter costs $\text{}\text{}75\text{}$. You pay with a $\text{}\text{}100\text{}$ bill. What bills do you get as your change?

$\begin{array}{llll}\hfill \text{}100-\text{}75& =\text{}25\phantom{\rule{2em}{0ex}}& \hfill & \phantom{\rule{2em}{0ex}}\\ \hfill & =\text{}20+\text{}5\phantom{\rule{2em}{0ex}}& \hfill & \phantom{\rule{2em}{0ex}}\end{array}$ Your change is a \$$20$ bill and a \$$5$ bill.

There are a lot of ways to combine bills. For example, you can get $\text{}\text{}70\text{}$ by combining a $\text{}\text{}50\text{}$ bill and a $\text{}\text{}20\text{}$ bill. You can also do this by combining seven $\text{}\text{}10\text{}$ bills. Can you think of other combinations to get $\text{}\text{}70\text{}$?

Here are some other combinations that give you \$$70$:

• Three \$$20$ bills and one \$$10$ bill.

• Four \$$10$ bills, one \$$20$ bill and two \$$5$ bills.

• One \$$50$ bill and four \$$5$ bills.

• One \$$50$ bill, one \$$10$ bill and two \$$5$ bills.