Skill: Solve purchase problems

To solve a purchase problem:

1. Find the cost of each item.
2. Add the costs to find the total.
3. Compare the total with the amount paid.
4. Subtract to find the change.

Example: Mia buys a notebook for 2.35$and a pencil for$$0.65$. She pays with$$5.00$. How much change does she get?

Step 1: Add the prices.
Keep the dollars and cents lined up:

$$\begin{array}{r} \$2.35\\ +\$0.65\\ \hline \$3.00 \end{array}$$

The total cost is 3.00$.

Step 2: Check if Mia has enough money.
She has 5.00$, which is more than$$3.00$, so she has enough.

Step 3: Subtract the cost from the amount paid.

$$\begin{array}{r} \$5.00\\ -\$3.00\\ \hline \$2.00 \end{array}$$

Mia gets 2.00$ in change.