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

÷10 100 | 40 ÷ 10

25 | 10

**1%**

% | Apples

÷100 100 | 40 ÷100

1 | 0.4

**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

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.

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