Benton's Percent Post

 A percent is an equivalent fraction out of 100.

 Here is how we find percents, in this example there are 40 apples.
 The 100% of the apples is 40/40
 We will be finding 50%, 25%, 10% and 1% using ratio tables.

          50%
          %   | Apples
÷2   100 | 40 /÷
     50  |   20

         25%
            %  |  Apples
÷ 4     100  |   40   /÷
    10   |    4

        10%

         %   |  Apples
÷10     100  |    40  ÷ 10
    25   |    10

     1%
         %    | Apples

÷100      100 | 40    ÷100

     1   | 0.4

Representing Percents
1) 180%

2) 12 3/4%

3) 0.7%

 

Converting Fraction-Decimal-Percent

1) 26%

26 ÷ 100 = 0.26

0.26 x 100 = 26/100

2) 7/10

7 ÷ 10 = 0.7

0.7 x 100 = 70%

3) 0.024

0.024 x 100 = 2.4%.

2.4/100

Percents

Calculator: 60 - 80% = 12                                                      Mental Math:  60 ÷ 5 = 12

                                                                                                                       100 ÷ 5 = 20

                                                                                     

               2) 0.1% of 40

 

Calculator: 40 ÷ 100 = 0.4                                                   Mental Math: 40 ÷ 1000 = 0.4

                                                                                                                  100 ÷ 1000 = 0.1

                3) 250% of 400

Calculator: 400 x 2.5 = 1000                                             Mental Math: 400 x 2 = 800 | 400 ÷ 2 = 200

                                                                                                                  800 + 200 = 1000
                                                                                                                  100 x 2 = 200 | 100 ÷ 2 = 50

                                                                                          200 + 50 = 250

Combining Percents

4.4 Pg. 149

7. 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.
b) Explain why there was not a 30% increase in population over the two years.

a)The population of the caribou herd after the second year was 132

The caribou herd's numbers increased by 10% the first year creating a total number of 110 caribou. The second year, the herd of caribou, now numbering 110 in total increased it's numbers by 20% for a total of 132 caribou at the end of the second year.

b) There was not a 30% increase in population over the two years because the 100% changed instead of remaining static. The 100% increased from 100 to 110 by the end of the first year and then there was a 20% increase of the current 100% raising the 100% to 132.

Discount is the money you save.

Sale Price is what you pay at the end.

4.4 Pg.148 Show You Know

 What is the final sale price at each store? Which is a better buy? Explain your thinking.

Store A: 50% off one day only
Store B: 25% off one day followed by 25% off the reduced price the second day

Example: you want to buy a $60 pair of boots.

Store A

Since 50% is equal to half, we can just half the number in question.

60 ÷ 2 = 30

The sale price is 30$

                                                  

Store B

First Day. As 25% is equal to a quarter, we can simply divide the number by 4.

60 ÷ 4 = 15                   60 - 15= 45

The sale price is now 45$

          Second Day.  We now divide the 100% (now 45$) in 4 again.

 45 ÷ 4 = 11.25                  45 - 11.25 = 33.75

The sale price is now 33.75$

Which is a better buy?

Store A is a much better choice because they're offering a $30 pair of boots compared to Store B's price of 33.75.

Joanna's Percent Post

What is a percent?

Percent is an equivalent fraction out of 100.
Here is how we find an equivalent fraction out of 100.

  9/10 = 90/100
  9 x 10 = 90                 Why 100%? 100 is used because it's just right. It is also a number that is
  10 x 10 = 100                                                            easily seen.

Percent was made by the French. Per means 'out of' in French and Cent means '100'. Together, they make 'out of 100'. For the percent symbol %, the line symbolizes the 1 while the two little circles represents the two zeros from 100.

Improper or Top Heavy fractions are fractions that have a greater numerator than the denominator.
205/100 = 2 wholes, 205 out of 100, 205%
5/4 = 5 out of 4, 125 out of 100, 125%

100% means all, whole, everything, 100/100, 6/6.
10% means 10/100, 1/10.
50% means half, part / whole, 20/40 or 50/100.
25% means 25/100, 1/4, one quarter.
1% means 1 out of 100, 1/100.

Representing Percents %

a) 180%

                                         












b) 0.6%

c) 12 3/8%

Fractions - Decimals - Percents

Fractions and converting them into decimals and percents...

1) 3/40 

Decimals: 3 ÷ 40 = 0.075

Percents: 0.075 x 100 = 7.5 

               0.075    /     1

       0.075 x 100 / 1 x 100

                7.5    /    100

3/40 --> 0.075 --> 7.5/100

Decimals and converting them into fractions and percents...

2) 0.086

Fractions:               43 / 500 

                                How?

                         0.086 / 1

            0.086 x 1000 / 1 x 1000

                            86 / 1000

                     86 ÷ 2 / 1000 ÷ 2

                          43 / 500

Percents: 43 ÷ 500 = 0.086 0.086 x 100 = 8.6%

0.086 --> 86/1000 or 43/500 --> 8.6%

Percents and converting them into decimals and fractions...

3) 33%

Decimals: 33 ÷ 100 = 0.33

Fractions:     33 / 100

                       How?

                 0.33 / 1

      0.33 x 100 / 100

                  33 / 100

33% --> 0.33% --> 33/100

PERCENT OF A NUMBER

                  1) 20% of 60

Calculator: 20 ÷ 100 = 0.20                            Mental Math:   #   |  %   

0.20 x 60 = 12                                                                           60 | 100  

                                                                                      ÷ 5       12 | 20    ÷ 5

20% of 60 = 12                                                                     12% of 60 = 12

A way of finding a percent of a number is to divide. Of means divide. In other words, you are multiplying 20% to 60, but what is 20% as a number? In order to do that, you have to divide your percent by 100. After that, you multiply your decimal to your number or whatever amount you have.

               2) 0.1% of 40

Calculator: 0.1 ÷ 100 = 0.001                         Mental Math:    #   |   %

0.001 x 40 = 0.04                                                                      40  | 100               

                                                                                ÷ 1000    0.04  | 0.1   ÷1000       

                                                                                             0.1% of 40 = 0.04

Since 0.1% is less than 1 and you know that 1% of 40 is 0.40, you should have something that is less than 0.40.

When dividing by 10, 100, 1000, etc, you move the decimal to the left by how many zeros are in the number. 

60 ÷ 100 = 0.60

          6 0 . 0 = 0.60

                                                                            ^ ^ ^   - move to two place values since 100 has 2               

                                                                                                                 zeros.

                3) 250% of 400

Calculator: 250 ÷ 100 = 2.50                           Mental Math:    #  |   %  

2.5 x 400 = 1000                                                                      400 | 100

                                                                                       x 2     800 | 200   x 2

                                                                                      ÷ 4     200  | 50     ÷ 4

                                                                                            + 1000 | 250

                                                                                        250% of 400 = 1000

Since 250 is greater than 100, you'll end up having more than you total.

             What you do on one side, you do to the other.

Combing Percents %

When you are working with money, you may often see discounts, sale prices, or regular prices...

Discount - What you save

Sale Price - What you pay

When finding the sale price...

Regular Price - Discount = Sale Price

When finding the total price including the taxes...

Step 1) Calculate the total prices of the item(s) that were bought.

4.4 Page 149

7.  A herd of 100 caribou 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.

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

             a) The population of the herd of caribou was 132. How?

                                

1. For finding the increase of the caribou, first thing's first is to add 100 + 10 since 'increasing' means to end up having more than what you had before. This tells you that for your answer, you should have a number that's more than the regular amount of caribou. 
2. After that, you need to take the percents that were from the question and convert them into a decimal. By doing so, you would have to divide the percent by 100.
3. Last part is to multiply the decimal to the total amount of caribous.

                            100 + 10 = 110                 110 ÷ 100 = 1.10              1.10 x 100 = 110

                                100 + 20 = 120              120 ÷ 100 = 1.2            1.2 x 110 = 132

                     b) The reason why 30% was not used because 100% was changed. From the first photo, the total amount of caribou were 100, but since we needed to make another diagram, the total was not 100 anymore because it was changed to 110 instead.

4.4 Page 148 Show you know

What is the final sale price at each store? Which is a better buy? Explain your thinking.

Store A: 50% off one day only

Store B: 25% off one day followed by 25% off the reduced prince the second day

Store A:

Price - $200 for a guitar

200 ÷ 2 = 100

Why 2? I used 2 because the 2 represents half of the number and in decimals, half equals 0.5.

or

50 ÷ 100 = 0.50              0.50 x 200 = 100 

The final price of the guitar in Store A is $100.

Store B:

Price - $200 for a guitar

25 ÷ 100 = 0.25       0.25 x 200 = 50        200 - 50 = $150 

   25 ÷ 100 = 0.25         0.25 x 150 = 37.5        150 - 37.5 = $112.50

First, you'll need to convert your percent, in this case it is 25%, to a decimal. In order to do that, you'll need to divide your percent out of 100 since percentage is out of 100%. 

25 ÷ 100 = 0.25

Second, you will need to solve what 25% is out of 200. To do that, you need to multiply the decimal to the total which is 200.

0.25 x 200 = $50

Now, you have found what 25% is out of 200 but you do not know how much you pay. Since we are working with money, 25% is what you save. You aren't done till you have your sale price. To find your sale price, you need to subtract 25% of 200 from $200.

200 - 50 = $150

You now have the sale price of the guitar of that one day. Next step is to find another 25% off from the sale price on the second day.

Again, you'll need to convert the percent into a fraction and multiply the given decimal to the sale price, which is 150.

25 ÷ 100 = 0.25                     0.25 x 150 = 37.5 or $37.50 

After that, you will need to subtract 25% of the reduced price and subtract it from the sale price, $150.

150 - 37.5 = 112.5 or $112.50

Which is a better buy? Buying the guitar from Store A is a better buy because you are saving $12.50 if you don't buy it from Store B. The reason why Store A was better than Store B was because of how the total of 100 was changed to 150 which caused it to have a bigger amount. Since Store B has a greater total or all than Store B, it will end up saving less than what Store A is saving.

Rafael's Percent Post

Percents mean:                       Rafael Nieves    Room 8-14       Math

1. Percents mean - Per (out of a) cent (hundred)

Why 100%? Because it is not only a friendly number, it is also just about right. Not to big, not to small, about in the middle.

What about 205% - 2 wholes
                              - equivalent fraction --> 205/100
                              - improper or top heavy

Means....(by T-Charts)

1% means - 1% of 100%
                 - 1/100

10% means - 10% of 100
                   - 100/10 or 40/10
                   - Divides by 10's

25% means - 25% of 100
                   - 100/4 or 40/4
                   - Half of 50
                   - Divides by 4's

50% means - 50% of 100
                   - 100/2 or 40/2
                   - Half
                   - Divides by 2's

100% means - 100% of 100%
                     - all, whole, everything, 1/100, /100

Symbol presents...

- Line in between the two zero's is the number one. It is also the divider for fractions.
- The two zero's represents the ends of the number 100

2. Representing Percents

• 180%
  

• .6%

• 12 3/8%

3. Representing and Converting

Mental Math

Calculator

1. 60/100 = 0.6 x 20 = 12

2. 40/100 = 0.4 x 0.1 = 0.004

3. 400/100 = 4 x 250 = 1000

4. Combining Percents

Discounts is what you save.
Sale Price is what you pay.

Sale price Solution, Regular- Discounts= Sale Price

Taxes

Ex. GST 5%
       PST 6%
               ----
              11%

100 + 11 = 111/100 = 1.11 then multiply to the money.

EXAMPLE:

     

Katrina's Percent Post

1.Percent Means
Equivalent fraction out of 100, per(out of), cent(100)

Why did we use 100% than 1000%
They use 100% because its easy to picture it than 1000%, 200%, 2000%, etc.



100% means any whole, everything, 100/100.

10 means 10/100. Divide it by 10

50% means half. Divide it by 2

25% means 25/100, divide it by 4,

1% means 1/100, divide it by 100.



205/100 or 5/4
Its an improper fraction which means the numerator is bigger than the diameter is. Some people call it Top Heavy.

2.Representing Percent

180%

0.6%

12 3/8% 

3.Converting


Fraction, Decimal, Percent

35 out of 50    35/ 50= 0.66   0.66 x 100= 60%



Decimal, Percent, Fraction


0.0064/1= 0.64/100 or 0.64  0.64 x 100= 64%  64/ 100


Percent, Decimal, Fraction

750%     750/100= 7.5     75/10 or  7 1/2


4.Solving Percent(mental, calculator)

Mental Math                                                                                                    Calculator

                                 
1. 20% of 60

                2. 0.1% of 40  

      3. 250% of 400      







5.Combining Percents


When you are working with money you will see discounts, sale price or regular price, and savings.
Discounts is what you save.
Sale Price is what you pay.

To find the sale price, Regular- Discounts= Sale Price


To find the total taxes, add the taxes into a hundred and add.

example.

What is the final sale price at each store? Which is a better buy?



Store A $10.50: 50% off one day only.

50/100=0.5 x 10.50= 5.25

Store B $10.50: 25% off one day followed by 25% off the reduced price the second day.

Day1.                                                                                                                       Day2.

Which is a better buy?
StoreA is a better buy because theyre offering us $5.25 comparing to StoreB we have to pay $7.88 in the first day but in the second day they offered us 25% again which make the sale price a little lower. But StoreA is better because we have to pay $5.25 its lower than $5.91 or $7.88

Julien's Percent Post

Percent means.......
 percent is a french word. "per" means out of  and cent means "100" 

 equivelent fraction out 100 

100 percent means all, whole everything  40/40 or 100/100

50 percent means half of the whole

25 percent means a quarter of the whole 

1 percent means one piece of the whole 

 we use 100 for percentage because it is just right.



1) 3/40 = 0.075/1 = 75 out of one hundred or 75 percent

2) 5.98/1 = 598/100 or 598 percent   598/1000

3) 750 percent/100 = 7.5 = 7 5/10 or 7 1/2


180%

 12 3/4 percent

0.7%

convert from decimals to fractions to percents.
26%
26/100=0.26
26out of one hundred.

7/10
7/10=0.7
0.7x100=70%

0.024
0.024x100=2.4out of one hundred
2.4x100=0.024

Mental Math and  a  Calculator
20% of 60 = 12
100/5=20
60/5=12

0.1% of 40=0.4
40/100=0.4

250% of 400=1000
400x2.5=1000


Discounts
q.3 pg.148
kyle is not correct because when you use the 15% and 10% it adds up to being less than the 30%.