Mathematics some questions about percent

To you know about percent you had toknow about the mathematics operation

+ sum,

- subtraction,

× multiplication,

÷ division.

Percent have a fraction but a specific denominator that is ‘one hundred’ so is a number divided by 100; 70% is the same of 70/100; 99% is the same that 99/100, fraction and division.

And you know now what is 80% and 55%, that is 80/100 and 55/100 or 0,8 or 0,55.

If you want to know 80% of 1.000 of liters or money, or oxygen, or hours, you multiply 1000 by 80%  that is in a paper this 1.000×80/100=800; 15% of 20.000 is the same that 20.000×15/100=3.000. Multiplication

So now you know how to find the percent of anything.

When you are in a store the person give you 20% of discount, that is like

 You multiply the value for the rest of the 100% - 20% = (100 – 20)%, if you take 20 of 100 rest 80, so is 100/100 less 20/100 that is the same that 80/100, so discount of 20% you pay 80%.

So you could direct multiply for 80/100;

You could subdivide for 20/100 and the result subtract from the value.

20% less of 5.000 is

1) 100% - 20% =80% that you multiply for 5.000,

1.1) 5.000×80%

 1.2) 5.000×80/100

1.3) 5.000×0.8

The result is 4.000

Or you could

1) subtract 20% from 5.000 like this,5.000 is 100% and find the 20% that is 1.000 so 100% less 20% is for 5.000, 5.000 - 1.000 that is 4.000 the same result.

Now you subtract with percentage.

You gonna receive 20% that you receive, so receive plus 20% is 100% + 20% = 120% (100 + 20)% = 120%, you just sum like there isn’t the symbol %, is a normal sum the same for subtract. You will increase a recipe for 30% so you gonna sum to the 100% (that is the total) + 30% that is 130%.

For plus 40% of 5.000, You could multiply for 140% or 1,4 or 140/100. That is 7.000

Or sum 5.000 with the result of 40% that is 5.000 + 2.000 that is 7.000

Now you know sum.

Percent with multiples you just multiply 100% for the multiple, double that is 2×, triple that is 3×, quadruple that is 4× and so it goes; is 2×100% that is 200%, 3×100% that is 300%, and 4 × 100% that is 400% and so on.

Parts: 20% is the same that 1/5, 20/100 if you simplify 20/100 will came 1/5, 20÷4/100÷4 = 1/5, 80% is like you multiply 1/5 by 4 that is 4/5, 4/5 + 1/5 is 5/5 that is 100% again.

The total of anything is 5/5 or 2/2 or 7/7 or 10/10, that is the same that 100% you know that 5/5 is the same that 1 and now you know that 100% is the same that 1.

Half in percent is 50% you just divide the 100% for the fraction you want so you want one third you subdivide 100% by 3, 100%/3, (100/3)% that is 33,33…%, you divide 100 by 3 and keep that percent simple like that.

100% = 1

99% = 0.99

Half of something 50%

80% same that 4/5

The double plus half of something is 250%, something plus the double and half is 350%.

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