6 ways to calculate the percentage of the sum calculator with and without

1. How to calculate the percentage by dividing the number of 100

So you find a numerical equivalent of 1%. Then it all depends on your goals. To calculate the percentage of the amount multiply them by a size of 1%. To convert to a percentage number, divide it by the resolution of 1%.

EXAMPLE 1

You go to the supermarket and see the action on the coffee. Its regular price - 458 rubles, now there is a discount of 7%. But you have a store card, and on it a pack will cost 417 rubles.

To understand which option is more profitable, it is necessary to transfer 7% in rubles.

Divide 458 by 100. To do this, you just need to move the comma separating the integer part from the fractional, two places to the left. 1% equals 4.58 rubles.

Multiply 4.58 by 7 and you get 32.06 rubles.

It now remains to take away from the regular price of 32.06 rubles. On shares of coffee will cost 425.94 rubles. So, it is more profitable to buy a map.

EXAMPLE 2

You see the game on Steam is worth 1000 rubles, while previously sold for 1500 rubles. I wonder how much interest was off.

Unit 1 500 100. Shifting comma two positions to the left, you get 15. This is 1% of the old price.

Now a new share price at the rate of 1%. 1 000 / 15 = 66,6666%.

100% - 66.6666% = 33.3333% discount .Such given store.

2. How to calculate the percentage by dividing the number by 10

This method is similar to the previous one, but consider using it much faster. But only if we are talking about percentages, multiples of five.

First you find the size of 10%, then divide and multiply it to get the right amount of interest.

Example

Let's say you put on deposit 530 000 rubles for 12 months. The interest rate is 5%, capitalization is not provided. You want to know how much money will take one year.

First we need to calculate 10% of the amount. Divide it by 10 by moving a comma to the left by one character. You will receive 53 thousand.

To find out how much make up 5%, divide the result by 2. This is 26.5 thousand.

If in the example it was about 30%, would have to be multiplied 3 to 53. To calculate the 25% it would have to multiply 53 by 2 and add 26.5.

In any case, such large numbers is quite simple to operate.

3. How to calculate the interest, amounting to a proportion

Be proportion - one of the most useful skills that you have learned in school. It can be used to calculate any interest. Looks proportion as follows:

the sum is 100%: 100% = the sum of the: the share percentage.

Or it can be written as follows: a: b = c: d.

Typically, the proportion is read as "and refers to b as well as c refers to d». The product of the extreme members proportions equal to the product of its average member. To find an unknown number of this equation, it is necessary to solve a simple equation.

EXAMPLE 1

For example, the calculations use the recipe quick brownie. You want to cook it, and bought a bar of chocolate a suitable weight 90 g, but could not resist and took a bite or two. Now you only have 70 grams of chocolate, and you need to know how much oil to put in place of 200 g

First, we calculate the percentage of the remaining chocolate.

90 g: 100 g = 70%: X, wherein X - of the remaining chocolate mass.

X = 70 × 100/90 = 77.7%.

Now accounts for the proportion to figure out how much oil we need:

200 g: X = 100%: 77.7%, wherein X - the desired amount of oil.

X = 77,7 × 200/100 = 155.4.

Consequently, the dough to put about 155 grams of oil.

EXAMPLE 2

Proportion suitable for calculating the profitability of discounts. For example, you see a shirt for 1499 rubles at a discount of 13%.

First, find out how much it costs blouse as a percentage. For this subtract 13 from 100 and receive 87%.

Make proportion: 1499: X = 100: 87.

X 1 = 87 × 499/100.

Pay 1 304.13 rubles, and wear a blouse with pleasure.

4. How to calculate percentages by relations

In some cases, you can use simple fractions. For example, 10% - this is the number 1/10. And to find out how much it will be in numbers enough to share a whole by 10.

• 20% - 1/5, that is, you need to divide the number by 5;
• 25% — 1/4;
• 50% — 1/2;
• 12,5% — 1/8;
• 75% - it's 3/4. Hence, it is necessary to divide the number by 4 and multiply by 3.

Example

You find trousers for 2400 rubles with 25% discount, but you have in your wallet only 2000 rubles. To find out if enough money on new clothes, perform a series of simple calculations:

100% - 25% = 75% - the cost of trousers as a percentage of the original price after applying the discount.

2 400 / 4 × 3 = 1 800. That's how much rubles worth pants.

5. How to calculate the percentage using the calculator

If the calculator without you life is not sweet, all calculations can be done with it. And you can do it even easier.

• To calculate the percentage of the amount, type a number equal to 100%, the multiplication sign, and then the desired percentage and the% sign. For example a coffee calculation would be: 458 × 7%.
• To find out the amount, exclusive of interest, enter the number equal to 100% minus the percentage of the size and the% sign: 458 - 7%.
• Similarly, one can add, as in the example with a deposit: 530 000 + 5%.

6. How to calculate the interest using online services

Not all of the interest can be calculated in the mind and even a calculator. When it comes to the contribution of return overpayments on the mortgage or taxesIt requires complex formulas. They accounted for some online services.

Planetcalc

The site contains various calculators to calculate not only the interest. There are services to lenders, investors, entrepreneurs and all those who do not like to consider in my mind.

Planetcalc →

Calculator - reference portal

Another service with calculators for every taste.

Calculator - reference portal →

Allcalc

Catalog online calculators, 60 of which are designed to calculate the finance. You can calculate the taxes and penalties, the amount of subsidy on utility services and much more.

Allcalc →

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