# Decimal Operations

### Study Guide Review

## Steps

2. Add zeros to any blank spaces

3. Add or subtract starting at the right

4. Bring down the decimal point

## Steps

2. Multiply the numbers together *(Forget about the decimals for now!)*

3. Count the decimal places in each number

4. Scoop the decimal point in the answer

## Steps

*(Hint: Scoop the decimal point to the right)*

2. Scoop the decimal point the same number of places in the dividend

3. Bring up the decimal point

4. Now divide!

## The Best Deal

## How do I find it?

*(Hint: Percents are always out of 100)*

2. Compare all of the percents. Which percent is the highest?

*(Hint: The highest percent will give you the greatest discount or the best deal!) *

3. Compare the percent and the dollar amount by converting the dollar amount to a percent *($ Off divided by Total $) *OR by converting the percent to a dollar amount *(Change the percent to a decimal and multiply the total amount of $ by the decimal)*.

## Calculating Sales Tax

## Steps

**Change**the percent to a decimal

*(Hint: Remember to scoop the decimal point two places to the left.)*

2. **Multiply** the original price by the decimal to find the tax

*(Hint: Remember to round the decimal to the nearest cent!)*

3. **Add **the tax to the original price for your final cost

## Calculating Tip

## Steps

**Change**the percent to a decimal

*(Hint: Remember to scoop the decimal point two places to the left.)*

2. **Multiply** the original price by the decimal to find the tax

*(Hint: Remember to round the decimal to the nearest cent!)*

3. **Add** the tip to the original price for your final bill

## Calculating Discounts

## Steps

**Change**the percent to a decimal

*(Hint: Remember to scoop the decimal point two places to the left.)*

2. **Multiply** the original price by the decimal to find the tax

*(Hint: Remember to round the decimal to the nearest cent!)*

3. **Subtract** the discount from the original price

## Rates & Ratios

**A**

**ratio**is a relationship between two numbers by division.

A **unit rate **is a ratio with the number one in the denominator.

## Proportions

**Proportions**are two ratios that are equal to one another.