Trisha's Percent Post

Hi this is my percent post!!

1.

• 50% - To find 50% of a number, you divide the number by 2.

• 10% - To find 10% of a number, you divide the number by 10.

• 1% - To find 1% of a number you divide the number by 100.

• 25% - To find 25% of a number you divide the number by 4.

• A percent is a number out of 100 or a whole. 

2.

• 180%

 

•  12 3/4%

• 0.7%

3.

• 26%

To convert a percentage to a decimal you have to divide the percentage by 100.  
Percent to Decimal: 26% ÷ 100 = 0.26

To convert a percent to a fraction you will have to first convert it to a decimal number (0.26), then you cross out the zero(s) (26) to get the numerator. In order to get the denominator of the fraction, you look at the place value of the last digit in the decimal number (hundredths). 

Percent to Fraction: 26/100

                

•  7/10

To convert a fraction to a decimal, you have to divide the numerator by the denominator

Fraction to Decimal: 7 ÷ 10 = 0.7

To convert a fraction to a percent you will have to first convert the fraction into a decimal number. Then you multiply the decimal by 100 to get the percentage. 

Fraction to Percent: 0.7 x 100 = 70%

• 0.024

 To convert a decimal number into a percent, you multiply the decimal by 100. 
 Decimal Percent: 0.024 x 100 = 2.4%

To convert a decimal number to a fraction, you cross out the zero(s) (24) to get the numerator, to get the denominator you look at the place value of the last digit of the decimal number (thousandths).

Decimal to Fraction: 24/ 1000

 4.

•  20%  of 60 = 12

     Mental Math:  10% of 60 = 6            ( 10% x 60 = 600

                             10% of 60 = 6              600 ÷ 100 = 6)

                                   6 + 6 =  12

     Calculator:      20% ÷ 100 = 0.2

                             0.2 x 60 = 12

• 0.1% of 40 = 0.04

 Mental Math: 40 ÷ 10 = 4 
                         4 ÷ 100 = 0.04
                        

   Calculator:     0.1% ÷ 100 = 0.001

                          0.001 x 40 = 0.04

• 250% of 400 = 1,000

 Mental Math:   100% of 400 = 400
                          100% of 400 = 400
                            50% of 400= 200

                            400+ 400 + 200 =  1000                     

  
Calculator:      250% ÷ 100 = 2.5

                         2.5 x 400 = 1,000


 5.
 Question 7 on page 149: A herd of 100 caribou was moved to a new location. The population increased by 10% the first year and then increased by 20% the second year.

A) Find the population after the second year. 
 10% ÷ 100 = 0.1
0.1 x 100 = 10
100 + 10 = 110

20% ÷ 100 = 0.2
0.2 x 110 = 22
110 + 22 = 132

B) Explain why there was not a 30% increase in population over the two years. 

There was not a 30% increase in population over the two years because the population wouldn't be accurate, it would be less than the actual population over the two years with the 10% increase in the first year and the 20% increase in the second year. 

30% ÷ 100 = 0.3
0.3 x 100 = 30
100 + 30 = 130 

 

Nicole's Percent Post

this is my percent post????????????!!!!!

1.

• 50% - To find 50% of a number, divide by 2.

• 10% - To find 10% of a number, divide by 10.

• 1% - To find 1% of a number, divide by 100.

• 25% - To find 25% of a number, divide by 4, or divide 50% of the number by 2.

The definition of percent: Percent means out of 100 and is another way of saying hundredths. ex. 30% means 30/100 or 0.30.

2. I didn't understand this question because I thought you had to do 3 examples for each.... But either way, the circle graphs are pretty accurate since I used a graph program. (yay for me)

• 180%

• 12 3/4%

• 0.7%

3.

• 26%
  Decimal- To convert 26% into a decimal, you must divide the number by 100. This is because percent means out of 100.
  26÷100=0.26
  Fraction- To convert 26% into a fraction, you must first take it's equivalent as a decimal, (in this case, 0.26) and determine the place value of this decimal falls under. (Hundredths) therefore, this fraction will have the denominator of 100. The numerator is 26 for this case.
  0.26 is equivalent to 26/100
• 7/10
  Decimal- To convert 7/10 into a decimal, always remember that it basically means, in this case, 7 divided by 10.
  7÷10=0.7
  Percent- To convert 7/10 into a percent, you take the decimal, 0.7 and multiply by 100.
  0.7 x 100= 70%
• 0.024
  Percent- To convert 0.024 into a percent, you multiply it by 100.
  0.024 x 100= 2.4%
  Fraction- To convert 0.024 into a fraction, you determine the place value the number is in. This number is in the thousandths place, so the denominator will be 1000. The numerator is 24.
  0.024 is equivalent to 24/1000

4. 

• 20% of 60
  Mental-
  60÷10=6 (10%), 6 x 2 = 12 (20%)
  Calculator-
  60÷100=0.6 (1%), 0.6 x 20= 12 (20%)
• 0.1% of 40
  Mental-
  40÷100=0.4 (1%), 0.4÷10=0.04 (0.1%)
  Calculator-
  0.1÷100=0.001, 0.001 x 40= 0.04
• 250% of 400
  Mental-
  400 x 2= 800 (200%), 400÷2= 200 (50%). 800+200=1000 (250%)
  Calculator-
  250÷100=2.5, 2.5 x 400= 1000.

5.
Question #7 on page 149.
A herd of caribou was moved to a new location. The population increased by 10% the first year and the increased by 20% the second year.
a) Find the population after the second year.
First year-
100÷10=10 (10%)
100+10=110.
Second year-
110÷10=11 (10%)
11 x 2=22 (20%)

110+22=132

b) Explain why there was not a 30% increase in population over the two years.
The increase of caribou population is not 30% because the population on the second year (20%) was determined by the increase on the first year (10%).



~links/references~
I remember seeing this website when I was first learning about Decimals, Percents and Fractions. It's straight to the point and even though this may seem like a very "childish" website, it can help you when you're just having a brain-fart (in which I did while doing this assignment hahaha!)
http://www.mathsisfun.com/decimal-fraction-percentage.html

An interesting video. *gasp* He explains when trying to find the percent of a number, he replaces the "%" sign with a decimal, and moving it two places to the left, instead of just dividing by 100.
http://www.youtube.com/watch?v=Im0VnXfYSns&noredirect=1


badabing badaboom see you next time

Kamille`s Percent Post

how to find key percents:
1.

a) to find 50 % of a number you have to divide the number by two.

b) to find 10 percent of a number you have to divid the number by ten.

c) to find 1% of a number you have to divide the number by one hundred.

d) to find 25% of a number you have to divide the number by four.

 A percent is number out of a hundred or a whole.

2.

180%

12 3/4 %

0.7%







3.
26% Decimal- divide it by 100 (26/100=0.26)
Fraction- make the numerator the numbers after the decimal and use the place value of the last number a decimal. (26/100)
Percent-take the decimal (0.26) multiply by one hundred (0.26x100=26%)



7/10 Decimal-divide the numerator by the denominator
 (7/10=0.7)
Fraction-make the numerator the number after the decimal (7) Then take the place value of the last number as a denominator (100) so, it's 7 over 100
Percent-multiply the decimal (0.7) by 100 (0.7x100=70%)


0.024 Percent-multiply decimal number by 100 (0.024x100=2.4%)
Decimal- divide the percent by 100 (2.4/100=0.024)
Fraction-take the numbers after the decimal except the zeros (2,4) for the numerator. For the denominator take the place value of the last number (1000) so it's 24 over 10000.

4. Mental math- 10% of 60=6, 10%of 60=6, 6+6=12
Calculator- 20% of 60- 20/100=0.2, 0.2x60=12

Mental math-1% of 100- 100/100=0.1, 40-100=0.4, 0.1/10=0.1, 0.4/10=0.04
Calculator- 0.1% of 40- 0.1/100=0.001, 0.001x40=0.04


Mental math- 100% of 400 =400, 100% of 400=400, 25% of 400= 100, 25% of 400= 100, 400+400+100+100=1000
Calculator- 250% of 499- 250/100=2.5, 2.5x400=1000


5. Question 7 on page 149: A herd of caribou was moved to a new location. The population increased by 10% the first year and then increased by 20% the second year.

a) find the population after the second year.

10/100=0.1
0.1x100=10
100+10=110

20/100=0.2
0.2x110=22
110+22=132

b) explain why there was not a 30% increase in population over the two years.

There was no 30% increase over th two years because the population wouldnt be precise. It would be a smaller amount than the actual pupolation with 10% increased the first year and 20% increased the second year combined.

30/100=0.3
0.3x100=30
100+30=130


Video about how to convert decimals to fraction :
Hope this helps you !(:

Jenny's Percent Post

1. How to find Key Percents

• 50% - divide the number you want to find the percentage of by 2 to get 50%
• 10% - divide the number you want to find the percentage of by 10 to get 10% 
• 1% - divide the number you want to find the percentage of by 100 to get 1%
• 25% - divide the number you want to find the percentage of by 4 to get 25%

        A percent is a fraction out of a whole.

2. Representing Percents

        Image #1
180%
+  

^100%                                               ^ 80%
        
          Image #2
12 3/4%

^ 12.75%
         Image #3
0.7% (7 out of 10)

^ 0.7%

3. Converting Decimal to Percentages to Fractions

        Percent to Decimal:
Divide the percentage by 100(move decimal two spaces forward/to the right)

        Decimal to Percent:
Multiply decimal by 100(move decimal two spaces back/to the left)

        Fraction to Decimal:
Divide the numerator by the denominator 

        Decimal to Fraction:
Multiply the number by 10 after every number after the decimal

        Fraction to Percent:
Divide the numerator by the denominator then multiply by 100

        Percent to Fraction:
Remove percentage sign, then divide by 100

• 26%

Decimal: 0.26             Fraction: 26/100

(26 x 100 = 0.26)      (26 ÷ 100 = 0.26)

-----------------------------------------------------------------------------------------

• 7/10

Decimal: 0.7          Percent: 70%

(7 ÷ 100 = 0.7)     (0.7 x 100 = 70%) 

-----------------------------------------------------------------------------------------

• 0.024

Percent: 2.4%                   Fraction: 2.4/100
(0.024 x 100 = 2.4%)      (2.4 ÷ 100 = 0.0024)

4. Percentage of a number using Mental Math and a Calculator

• 20% of 60

          v                                                              60 ÷ 10 = 6(10%)

         10% of 60 = 6                                          6 x 2 = 12(20%)

                                     = 12

         10% of 60 = 6

-----------------------------------------------------------------------------------------

• 0.1% of 40

          v                                                               40 ÷ 10 = 4(10%)

         1% of 40 = 0.4                                          4 ÷ 100 = 0.04(0.1%)

-                                    

         0.5% of 40 = 0.2

-

         0.1% of 40 = 0.04

-                                         = 0.04

         0.1% of 40 = 0.04

-

         0.1% of 40 = 0.04

-       

         0.1% of 40 = 0.04

----------------------------------------------------------------------------------------

• 250% of 400

          v                                                   400 x 100 = 40 000

         100% of 400 = 400                       40 000 ÷ 40 = 1 000

+

         100% of 400 = 400      = 1 000

+

         50% of 400 = 200

5. Explaining Discounts, Sale Price, and Total Price with Taxes

Question #7 on page 149:
A herd of 100 caribou was moved to a new location. The population increased by 10% the first year, then increased by 20% the second year.

a) Find the population after the second year.
10(increase in the first year) ÷ 100 = 0.1        20(increase in the second year) ÷ 100 = 0.2
0.1 x 100 = 10                                                     0.2 x 110(total of first years) = 22
100 = 10 = 110(first year)                                110 + 22 = 132(second year)
                                                                                                 ^ total
b) Explain why there was not a 30% increase in population over the two years.
         A: There was not a 30% increase because if there was, it wouldn't make sense due to it would be 130 caribou in total in the end if there was the 30% increase but since it was 132 in total for the second year, it'd be confusing on how it's 132 one year and 130 the year after.

Here is a video of converting decimals to percent for anyone who has trouble (: My brother watched it and he is finally understanding how to convert a decimal to a percent just by watching this video once.