The expression percent, is everywhere. The
percentage is very useful in several arias, the financial market is used to
express inflationary and deflationary indices, discounts, increases, interest
rates, among others. In Engineering, the percentage can be used to define how
much has already been constructed in a building; Administration can be used to
measure the participation shares of the partners in a business.
Some examples:
- In 2006, Luis Inacio Lula da Silva was the
preference of 61% of the vote.
- The unemployment rate in Brazil grew 13% this
year.
- 25% discount on cash purchases.
- Gasoline increased by 15%
The term percent (%) to the ratios of
the resulting 100 is called proximate reason.
Percentage
|
Percent ratio
|
Decimal
number
|
1%
|
1/100
|
0,01
|
5%
|
5/100
|
0,05
|
8%
|
8/100
|
0,08
|
11%
|
11/100
|
0,11
|
15%
|
15/100
|
0,15
|
10,5%
|
10,5/100
|
0,105
|
20%
|
20/100
|
0,20
|
Example 1:
Maria threw out 20% of the 100
magazines she had. How many magazines were to waste?
100 x 20/100 (twenty percent) = 20 magazines
Therefore, two magazines were thrown off by Maria.
example 2
I bought 20 shirts to resell. The first exit I was
lucky and managed to sell 70%. How many pieces of
clothing I sold?
70% of 20 is 14 We arrived at this value by the
account below:
20. = 0.7 14
Therefore: I sold 14 of 20 shirts
Multiplication factor
Multiplication factor is an increase or a decrease
in the value of
product.
If a product has increased by
20% then its multiplication factor is 1 +
growth rate, such rate being 0.2. So your factor
multiplication is 1.2.
Below is a table of multiplication factors:
Increase or profit
Multiplication factor
Increase or
profit
|
Multiplication
factor
|
12%
|
0,88
|
17%
|
0,83
|
45%
|
0,55
|
48%
|
0,52
|
50%
|
0,50
|
example:
Selling a shirt that cost 50.00 with
a real increase of
10% are:
50 * 1.1 = 55.00 reais
If a product has a discount of 20%
then its multiplication factor
is 1 - decrease rate, such rate being 0.2. So your
factor
multiplication is 0.8.
Below is a table of multiplication factors:
Discount
|
Mulplication factor
|
12%
|
0,88
|
17%
|
0,83
|
45%
|
0,55
|
48%
|
0,52
|
50%
|
0,50
|
example:
Discounting 20% amounting to 50.00 reais, we have:
50 * 0,80 = 40,00 reais
