1.2.3 Performing calculations with percentage change

• 25% is equivalent to the fraction 1/4.

  True
• 1% as a fraction is 1/100.

  True
• What is the first step in calculating the percentage of a number?

  Convert to a decimal
• Match the percentage with its equivalent fraction and decimal:

  1% ↔️ 1/100 and 0.01

  10% ↔️ 10/100 and 0.1

  50% ↔️ 50/100 and 0.5

  100% ↔️ 100/100 and 1.0
• What is 20% expressed as a decimal?

  0.20
• To find the percentage decrease, divide the decrease amount by the new value.

  False
• The result of multiplying the decimal by the original number is the percentage of that number.

  True
• How do you convert a percentage to a decimal?

  Divide by 100
• Steps to calculate the percentage of a number

  1️⃣ Convert the percentage to a decimal

  2️⃣ Multiply the decimal by the original number

  3️⃣ The result is the percentage of the number
• What do you divide the amount of increase by in the second step of calculating percentage increase?

  Original value
• Steps to find the original value when given a percentage and its value

  1️⃣ Convert the percentage to a decimal.

  2️⃣ Divide the known value by the decimal.

  3️⃣ The result is the original value.
• Match the step with its action in calculating percentage increase:

  Step 1 ↔️ Subtract original from new value

  Step 2 ↔️ Divide increase by original value

  Step 3 ↔️ Multiply by 100 to convert
• What is the first step in calculating percentage decrease?

  Subtract new from original
• What three steps are involved in calculating percentage increase?

  Subtract, divide, multiply
• What is the price of an item after a 20% discount if it was originally priced at £100?

  £80
• What is 20% of 50?

  10
• What is the new monthly salary after a 5% increase if the original salary was £2,000?

  £2,100
• The result of dividing the known value by the decimal is the original value.

  True
• Arrange the steps for calculating percentage increase in the correct order:

  1️⃣ Subtract the original value from the new value

  2️⃣ Divide the amount of increase by the original value

  3️⃣ Multiply the result by 100
• A percentage increase of 50% means the value doubled from its original amount.

  False
• What do you divide the decrease amount by to find the percentage decrease?

  Original value
• A percentage decrease of 40% means the price has increased by 40% of its original value.

  False
• What is the final price of a product after adding 20% VAT if it was originally priced at £150?

  £180