# Percentages

### Finding the Percentage of a Number

### Video

This video from *Khan Academy* describes how to calculate a given percentage of a whole number, and shows how to return the answer in various formats.

Note: All *Khan Academy* content is available for free at www.khanacademy.org.

### Notes

Page **2** of these notes from MathCentre shows how to compute a given percentage of a number, along with some exercises with answers given at the end.

A pdf of this document can be downloaded here.

### Interactive Exercises

This NUMBAS exercise will let you practise what you’ve learned about calculating percentages of a number.

Please click here to view this NUMBAS question in another window.

### Changing from a Fraction to a Percentage and vice versa

### Video

This video from *Khan Academy* shows how to convert from a simplified fraction to a percentage. It also shows how to write the same fraction in decimal notation.

Note: All *Khan Academy* content is available for free at www.khanacademy.org.

This video from *patrickJMT* shows how to convert from a percentage to a simplified fraction.

Note: All *patrickJMT* content is available for free at www.youtube.com/user/patrickJMT.

Patrick JMT’s Website: www.patrickjmt.com.

### Notes

Page **2** of these notes from MathCentre shows how to convert from a fraction to a percentage and vice versa. There also exercises for you to practise with on page **3**.

A pdf of this document can be downloaded here.

### Interactive Exercises

This interactive exercise from NUMBAS lets you practise the conversion from fraction to percentage and vice versa.

Please click here to view this NUMBAS question in another window.

### Converting between Decimals and Percentages

### Videos

This video from *patrickJMT* shows how to convert a percentage to a decimal with a few different examples.

Note: All *patrickJMT* content is available for free at www.youtube.com/user/patrickJMT.

Patrick JMT’s Website: www.patrickjmt.com.

This *Khan Academy* video shows how to convert a decimal to a percentage with an example.

Note: All *Khan Academy* content is available for free at www.khanacademy.org.

### Notes

Page 1 of these notes shows how to convert a decimal to a percentage with examples, and has exercises with answers that you can use for practice.

A pdf of this document can be downloaded here.

### Interactive Exercises

This NUMBAS exercise is a multiple-choice questionnaire which asks you to select the correct decimal or percentage conversion in each instance.

Please click here to view this NUMBAS question in another window.

### Finding Percentage Change

### Videos

This video from *Mario’s Math Tutoring* shows how to compute the increase or decrease in percentage of an amount.

Note: All * Mario’s Math Tutoring * content is available for free at www.youtube.com/c/MariosMathTutoring.

Mario’s Math Tutoring Website: www.mariosmathtutoring.teachable.com.

### Notes

Pages 5-6 of these MathCentre notes give applied examples to show how to calculate the percentage increase or decrease of an amount.

A pdf of this document can be downloaded here.

### Interactive Exercises

You can test what you’ve learned with these NUMBAS exercises which cover adding percentage changes to the original amount, and calculating percentage changes.

Please click here to view this NUMBAS question in another window.

### Finding Original Amount Given Percentage Discount

### Videos

This video from *patrickJMT* shows the steps for solving a word problem in which you find the original price of an item before discount.

Note: All *patrickJMT* content is available for free at www.youtube.com/user/patrickJMT.

Patrick JMT’s Website: www.patrickjmt.com.

### Notes

These notes from the DeMontfort University MLC show how to find the original amount or price of an item given the percentage increase or decrease.

A pdf of this document can be downloaded here.

### Interactive Exercises

This NUMBAS exercise lets you practise how to compute the original price of an item given the current price and the percentage discount.

Please click here to view this NUMBAS question in another window.