percentages everything you need to know ….eventually

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PercentagesPercentages

Everything you need to know Everything you need to know ….eventually….eventually

Whether you are as clever Whether you are as clever as …as …

Or as dumb as ……Or as dumb as ……

No, I’m not saying you are No, I’m not saying you are stupidstupid

You need to write these You need to write these downdown

Percent means ….Percent means ….

‘‘out of a hundred’out of a hundred’

We can write any fraction We can write any fraction or decimal as a or decimal as a

percentage.percentage.

HopefullyHopefully by the by the endend of the of the lessonlesson

Example 1Example 1

17 = 17%17 = 17%

100100

Example 2Example 2

23 = 46 = 46%23 = 46 = 46%

50 10050 100

X2

X2

Example 3Example 3

17 = 85 = 85%17 = 85 = 85%

20 10020 100

X5

X5

Example 4Example 4

13 = 52 = 52%13 = 52 = 52%

25 10025 100

X4

X4

Example 5Example 5

8 = 80 = 80%8 = 80 = 80%

10 10010 100

X10

X10

Now for slightly more Now for slightly more difficult ones…..difficult ones…..

Relax I said slightly!Relax I said slightly!

Example 6Example 6

86 = 43 = 43%86 = 43 = 43%

200 100200 100

÷2

÷2

Example 6Example 6

96 = 32 = 32%96 = 32 = 32%

300 100300 100

÷3

÷3

Your turn…Your turn…

21 = 84 = 84%21 = 84 = 84%

25 10025 100

X4

X4

Your turn…Your turn…

12 = 60 = 60%12 = 60 = 60%

20 10020 100

X5

X5

One more …One more …

148 = 74 = 74%148 = 74 = 74%

200 100200 100

÷2

÷2

Wordy question…Wordy question…

If you score 46 out of 50 in a If you score 46 out of 50 in a maths test, what percentage maths test, what percentage

did you get?did you get?

Answer….Answer….

46 = 92 = 92%46 = 92 = 92%

50 10050 100

X2

X2

Before you start, just Before you start, just remember….remember….

Some people got more than Some people got more than that!that!

Can also change percentages Can also change percentages into fractions….into fractions….

48% = 48 = 1248% = 48 = 12 100 25100 25

(48 and 100 both divide by (48 and 100 both divide by 4)4)

And another…And another…

65% = 65 = 1365% = 65 = 13

100 20100 20

(65 and 100 both divide by 5)(65 and 100 both divide by 5)

One for you ….One for you ….

18% = 18 = 918% = 18 = 9

100 50100 50

We can even change We can even change percentages into decimals…..percentages into decimals…..

Really easy…..Really easy…..

Just divide by 100Just divide by 100

Example …..Example …..

53% = 53 = 53 53% = 53 = 53 ÷100÷100

100100

= 0.53= 0.53

Another one ……Another one ……

68% = 68 = 6868% = 68 = 68÷100÷100

100100

= 0.68= 0.68

Last one ……Last one ……

54% = 54 = 5454% = 54 = 54÷100÷100

100100

= 0.54= 0.54

That’s it for nowThat’s it for now

Time for a Time for a worksheetworksheet

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