Fractions, Decimals & Percentages Week 04: Fractions, Decimals & Percentages Calculating fraction parts Calculating percentage parts Using fractions and percentages to calculate increases and decreases when using money Converting between fractions, decimals and percentages Calculating and using equivalent fractions, decimals and percentages

What did we do last week?

Key Terminology anrctifo rceeepntag cedmali nuatorrme danmintoore queivantel fyimplis cireasen cereased allccuate Fraction Percentage Decimal Numerator Denominator Equivalent Simplify Increase Decrease Calculate

Converting Fractions, Decimals & Percentages Fraction to Decimal: numerator ÷ denominator Decimal to Percentage: x 100 Percentage to Fraction: percentage becomes numerator, denominator is 100. Simplify. Fraction Percentage Decimal

Complete these FDP conversions…

¼ Fractions Denominator: The total number of parts Numerator: The number of parts we are interested in

What is ¼ of 12?

Divide by the bottom number, multiply by the top Finding a fraction Calculate ¾ of 500. Divide by the denominator (bottom number) to get the value of ¼: 500  4 = 125 Multiply by the numerator (top number) to get the answer: 125 x 3 = 375 Divide by the bottom number, multiply by the top

Practice 3/8 of 32 ½ of 24 2/5 of 20 6/7 of 14

Exam question A £45 pair of jeans have 1/3 off the price in a sale. What is the sale price? Original Price: £45 1/3: 45 ÷ 3 = £15 New Price: £45 - £15 = £30 The sale price of the jeans is £30.

Equivalent fractions        

Making fractions Fractions are sometimes hidden in words instead of numbers: 60 learners were questioned in a recent survey and 15 were found to be smokers. Where’s the fraction? The total number = 60, the amount that were smokers = 15 = 15/60. Can the fraction be simplified? Yes! ¼ The survey found a quarter of learners smoked.

Making fractions Santander recently conducted a survey on their customers: 200 are 0 - 18 years old 400 are 19 - 24 years old 700 are 25 - 39 years old 900 are 40 - 64 years old 300 are 65+ years old What is the fraction of people between 19 and 39? 1300/2500 What is this fraction when simplified? 13/25

Percentage of an amount Use the percentage button on your calculator! What is 20% of 500? Type in 500 x 20% = You should get the answer 100. Alternative: Percent means ‘out of 100’, so divide by 100 then multiply by the percentage you are looking for: ÷ 100 = 5 5 x 20 = 100.

Percentage of an amount

Percentage increase and decrease Work out the percentages as before. Increase means ‘add on to’ and decrease means ‘take away from’: Account Holder 2016 Balance % Change 2017 Balance H. Solo £5, 102 10% increase K. Broflovski £80, 980 30% decrease S. Smith £32, 654 5% increase J. T. Kirk £200, 902 10% decrease £5, 612.20 £56, 686 £34, 286.70 £180, 811.80