# Calculating Percentage: Lesson 2

Note: The mini-lesson above has audio. It is the second in a series of three lessons on calculating with percent. It shows how to calculate a part of a whole given a percent – the example used finds what 30% of 450 is. The lesson shows how equal ratios can be used for the calculation. It also illustrates the problem and the concept using a double number line. Lesson #2

## Related Resources

The Percentages Lesson explained above is aligned with the standard 7RP03 from the Common Core Standards For Mathematics (see the shortened extract below). The resources below are also aligned to this standard.

Use proportional relationships to solve multistep ratio and percent problems. Examples: simple interest, tax, markups and markdowns, gratuities and commissions, fees, percent increase and decrease, percent error.

### Worksheet

Similar to the above listing, the resources below are aligned to related standards in the Common Core For Mathematics that together support the following learning outcome:

Analyze proportional relationships and use them to solve real-world and mathematical problems