Finding 100%

In this lesson, you will learn about how useful 100% is, and how we use it to solve various percentage problems.

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Question 1

Question 2

Question 3

Question 4

Question 5

Q1.If the amount of flour in a bag increased by 20%, it would always mean we add 20g on to the amount.

1/5

Q2.If I increase 200kg by 30%, then the new amount I have is...

2/5

Q3.The decimal multiplier to increase an amount by 53% would be...

3/5

Q4.It is possible to increase an amount by more than 100%

4/5

Q5.If you decreased an amount by 60%, the decimal multiplier would be 1.60.

5/5

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Question 1

Question 2

Question 3

Question 4

Question 5

Q1.If the amount of flour in a bag increased by 20%, it would always mean we add 20g on to the amount.

1/5

Q2.If I increase 200kg by 30%, then the new amount I have is...

2/5

Q3.The decimal multiplier to increase an amount by 53% would be...

3/5

Q4.It is possible to increase an amount by more than 100%

4/5

Q5.If you decreased an amount by 60%, the decimal multiplier would be 1.60.

5/5

Video

Click on the play button to start the video. If your teacher asks you to pause the video and look at the worksheet you should:

  • Click "Close Video"
  • Click "Next" to view the activity

Your video will re-appear on the next page, and will stay paused in the right place.

Worksheet

These slides will take you through some tasks for the lesson. If you need to re-play the video, click the ‘Resume Video’ icon. If you are asked to add answers to the slides, first download or print out the worksheet. Once you have finished all the tasks, click ‘Next’ below.

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Finding 100%

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Question 1

Question 2

Question 3

Question 4

Question 5

Q1.If 75% of a number is 150, what is my number?

1/5

Q2.If I buy a car in a 20% off sale and it costs £30,000, how much did the car originally cost?

2/5

Q3.If I decreased the amount I paid for my car insurance by 90% to £36.50 per year, how much did I pay previously for my car insurance?

3/5

Q4.If a jumper was marked as 56% off and costs £50 now, then 44% of the original cost of the jumper is equal to £50

4/5

Q5.If I know something costs £2.10 in a 30% off sale, then i would do £2.10 = 70% and scale accordingly to get that 100% = £3 to find the original amount.

5/5

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Finding 100%

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Question 1

Question 2

Question 3

Question 4

Question 5

Q1.If 75% of a number is 150, what is my number?

1/5

Q2.If I buy a car in a 20% off sale and it costs £30,000, how much did the car originally cost?

2/5

Q3.If I decreased the amount I paid for my car insurance by 90% to £36.50 per year, how much did I pay previously for my car insurance?

3/5

Q4.If a jumper was marked as 56% off and costs £50 now, then 44% of the original cost of the jumper is equal to £50

4/5

Q5.If I know something costs £2.10 in a 30% off sale, then i would do £2.10 = 70% and scale accordingly to get that 100% = £3 to find the original amount.

5/5

Lesson summary: Finding 100%

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