1. PERCENTAGES

2. Introduction Percentages are a special type of fraction based on 100 with their own language and symbols............ The symbol % means percent. 1% is defined as 1/100 (“one-hundredth”). To find 1% of a quantity simply divide by 100.

3. Percentages are Fraction ! Remember, a percentage is a fraction based on 100, you can use your fraction knowledge.. Can you fill in the gaps below ? 1% = 1/100 (“one-hundredth”) 23% = 23/100 (“twenty-three hundredths”) 39% = 50% = 50/100 = 1/2 75% =

4. Percentages as Fractions ! Remember, a percentage is a fraction based on 100, you can use your fraction knowledge.. 1% = 1/100 (“one-hundredth”) 23% = 23/100 (“twenty-three hundredths”) 39% = 39/100 (“thirty-nine hundredths”) 50% = 50/100 = 1/2 75% = 75/100 = 3/4 (“three-quarters”)

5. Quick Exercise Write the following fractions as percentages..... 1)10/1004) 41/100 2)40/2005) 54/600 3)49/7006) 64/800 Write the following percentages as fractions... 1) 3%4) 25% 2)83%5) 50% 3)40%6) 75%

6. Quick Exercise Write the following fractions as percentages..... 1)10/100= 10%4) 41/100 = 41% 2)40/200= 20%5) 54/600 = 9% 3)49/700= 7%6) 64/800 = 8% Write the following percentages as fractions... 1) 3% = 3/1004) 25% = 1/4 2)83% = 83/1005) 50% = 1/2 3)40% = 4/106) 75% = 3/4

7. Finding Percentages of Quantities Question Find 42% of 240 Divide 240 by 100 to find 1% = 2.4 42% = 42 x 1% = 42 x 2.4 = 100.8 Question Find 77% of 413 Divide 413 by 100 to find 1% = 4.13 77% = 77 x 1% = 77 x 4.13 = 318.01 In percentages everything works around 100 !

8. Finding Percentages Questions Find the following amounts... 1)25% of 5004) 50% of 112 2)30% of 1705) 75% of 1200 3)45% of 6246) 90% of 6300 Percentages are sometimes used to increase or decrease amounts...try these questions 1)Increase 200 by 12% 2)Decrease 450 by 10%

9. Finding Percentages Questions Find the following amounts... 1)25% of 500 = 125 4) 50% of 112 = 56 2)30% of 170 = 51 5) 75% of 1200 = 900 3)45% of 624 = 280.8 6) 90% of 6300 = 5670 Percentages are sometimes used to increase or decrease amounts...try these questions 1)Increase 200 by 12% 1% = 2, 12% = 24, add increase = 224 2)Decrease 450 by 10% 1% = 4.5, 10% = 45, subtract decrease = 405

10. SUMMARY Percentages are special fractions based on 100 1% means 1/100 “one-hundredth”. Cent.. means 100 e.g. Century, Centimetre. Percentages are used to find parts of a whole, and to increase or decrease quanitities. SUMMARY Percentages are special fractions based on 100 1% means 1/100 “one-hundredth”. Cent.. means 100 e.g. Century, Centimetre. Percentages are used to find parts of a whole, and to increase or decrease quanitities.