Percents Fractions Decimals by maclaren1

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									     PERCENTS

Fractions   Decimals
 Percentages are another form of a fraction
  and decimal – all 3 are parts to a whole.

• The % is “per hundred”
• For example, 47% is 47 per hundred

          47% =    47      = .47
                  100

     They all say the same thing.
   Decimal to Percentage

To change a decimal into a
percentage, you X by 100



0.23     X 100         23%
Another Example… .47           This is read as “47
                                  hundredths”


       100
                 MULTIPLY by 100
      x .4 7
      4700       Jump the decimal & drop the zeros




       47.       That leaves us with



                 change the decimal to a %
       47%
What do you notice about the decimal
and percent sign in relation to the
numbers?                   1.32    .547
  .47     .93     .86
  47%     93%     86%     132% 54.7%


 Decimals to Percents jump Right

           DP R          DP M
  Decimal to Percent jump Right.
              DPR

.23 =   23%      6.03 =   603%
.87 =   87%       .30 =    3%

.45 =   45%      .553 =   55.3%

1.23 = 123%      .329 =   32.9%
  Percentage to Decimal

To change a percentage into a
 decimal, you divide by 100



23%      ÷ 100        .23
    Percentage to Decimal you
      always DIVIDE by 100
 For example, 35% as a fraction is 35/100 so
to change this into a decimal, you divide 35 by
                      100

35%              ÷ 100                0.35
35%   ÷ 100
        .3 5
  100 35.00
      30 0     What do you
                notice about
                the percent
        5 00    sign and the
        5 00      decimal?
           0
   Percents to Decimals jump LEFT.
                 PDL

62% = .62         29% = .29

38% = .38          3.95% =.0395
46.2% = .462       29% = .29
6.2% = .062        .62% = .0062
   Finding the percentage of another quantity

Ann obtained a
score of 23 out
of 32 on a
science test.          To do this, you: FDP it
What is her            • Write as a fraction 23/32
percentage?            • Fraction to a decimal
                          (23 ÷ 32 = 0.71875)
                       • Decimal to a %
                          (0.71875 X 100 = 71.9%)
                        Leprechaun Car Survey
                          Color    Frequency
                          Green        2
                          Silver       4
                          Black        5
What percentage of
the cars are green?

    •Total as a FRACTION: 2/11
    • Divide into a DECIMAL: 0.1818
    •Convert to PERCENT: 18%
The percentage of a number…
What is 32 percent of 86?
                            •Rewrite
 Y   =     .32     x 86        PDL


          Y = 27.52         •Solve


          Y = 2752%         •Percent
25% of 32 = 8
                   6% of 220 = 13.2
75% of 36 =  27
               15% of 150 = 22.5
80% of 35 = 28
                  25% of 32 = 8
10% of 142 = 14.2
                  12% of 20 = 2.4
20% of 60 = 12
                    27% of 30 = 8.1
35% of 70 = 24.5

								
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