Percents etc...

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Representing Percents

A) ^ how many are shaded?

= 12%

B) How many squares are total?

= 100

C) Proportion of shaded squares to total numbers?

= 12:100 , 12/100

D) Fraction in smallest term?

= 3/25

Fractions, Decimals and Percents

Part 1: Fractions to Decimal to Percent (fraction-precent)

(7/2) 7/2 = 3.5 x 100 = 350%

Part 2 : Decimal to Percent and Fraction

1.17 x 100 = 127% / 127/100

(Can't simplify it but if possible then do it.)

Part 3 : Percent to Decimal and Fraction

750%/100 = 7.5 /

75/10 = 15/2

Sometimes there may be fractions within the square so do t/b = decimal then add

Percent Of A Number

A) Convert percent into a decimal

B) Multiply the decimal but the number

Examples

1. How much savings does 40% of 20$ provide?

= 40/100 = 0.4 x 20 = 8$ off

2. 160% of 53.27$

= 160/100 = 1.6 x 53.27

= 85.2$

3. 3/4% of 135$

3/4 = 0.75 ~ 0.0075 x 135

= 1.01$

Combining Percents

A) Method 1 : Separately

B) Method 2 : Tax % first

C) Method 3 : Cost + Tax %

Shoes cost 65$. What's the total cost with 5% GST and 7% PST?

5% + 7% = 12%/100 = 0.12

0.12 x 65 = 7.80 ~ 65 + 7.80

= 72.80$

Percent of a percent

Final sale at original price 100$

A) 50% off one day only

B) 25% one day followed by 25% the next

Store A

50% of 100 =

0.5 x 100 = 50

100 - 50 = 50$

Store B

0.25 x 100 = 25

100 - 25 = 75

0.25 x 75 = 18.75

75 - 18.75 = 56.25