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How to calculate percentages



Knowing how to calculate percentages will help you not only to get good results on a math test but also in the real world. They are used to calculate restaurant tips, find out the nutritional content of your food or even to determine statistics about your favorite sports team. Regardless of how you plan to use the knowledge, the calculation of percentages is basic and fairly easy overall.

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[ Edit ] Practice Problem

WH.shared.addScrollLoadItem (& # 39; 5f15bf81e20ba & # 39; 5f15bf81e20ba & # 39; ) Percentages Exercise Problems
WH.shared.addScrollLoadItem (& # 39; 5f15bf81e2d7f & # 39;) Calculate Percent Exercise Problems ANSWER KEY

[] Edit [19459907] Edit a whole picture

what a percentage represents. A percentage is an expression of a part of the whole. Nothing is represented by 0%, and the whole amount is 100%. Everything else is somewhere in between! [1]

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  • For example, say you have 10 apples. If you eat 2 apples, you have eaten 2 out of 10 apples (2/10 × 100% = 20% eaten). If 10 apples are 100% and you ate 20%, 100% – 20% = 80% of the apples are left.
  • The term "percent" in English comes from Latin percent which means "Even 100" or "for 100".
  • Determine the entire value. In some cases, you get the value for a part of the whole and the whole. Other times, you can get two parts that make up the whole. It is important to distinguish what the percentage is "off." For example, let's say we have a jar that contains 1199 red balls and 485 blue balls, which makes it 1684 balls in total. In this case, 1684 is a whole can of bullets, ie 100%. [2]
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  • Find the value you want to convert to a percentage. Let's say we want to find out the percentage of the can that is taken up by the blue balls. Then the percentage of the whole we are looking for is 485 (the number of blue balls) of 1684 (the whole amount). [3]
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  • Put the two values ​​in a fraction. The part goes to the top of the fraction (teller), and the whole goes to the bottom (the denominator). Therefore, the fraction in this case is 485/1684 (part / whole). [4]
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  • Convert the fraction to a decimal. Percentages are best calculated based on the decimal form. To convert 485/1684 to one decimal place, divide 485 by 1684 using a calculator or pen and paper. This comes to 0.288. [5]
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  • Convert the decimal to one percent. Multiply the result obtained in the step above by 100% (per 100 = percent ). For this example, 0.288 multiplied by 100% is equal to 28.8%. [6]
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  • [ Edit ] Work backwards from a percentage

    1. Identify the given number you are working with. Say you borrowed money from a friend who will charge your daily interest. The amount borrowed was initially $ 15 and the interest rate is 3% per day. These are the only two digits you need for the calculation. [7]
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    2. Convert the percentage to a decimal. Work backwards from before, divide the percentage by 100%, or you can multiply by 0.01 (they are exactly the same). 3% / 100% = 3/100 = 0.03. [8]
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    3. Reformulate the problem with your new values. It helps to reformulate your problem with the new values ​​now in the form of " X of Y is Z ." X is the decimal form of your percentage, "off" means multiplying, Y is the full amount and Z is the answer. So 0.03 x $ 15 is $ 0.45. [9]
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      • In this example, $ 0.45 is the amount that arises each day that you do not pay back to your friend.
      • If you need To further calculate the amount due after one day, add the amount you borrowed to the interest amount times the number of days. So $ 15 + ($ 0.45 x 1 day) = $ 15.45.

    [ Edit ] Calculating Discounts

    1. Write down the original price and discount percentage. The initial price is usually the large number that retailers will notice or make particularly large so that you know how good a "deal" you are getting. [10]
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      • Make sure also pay attention to whether the discounted percentage applies to a single item or the total.
    2. Find the opposite of the discount percentage. This trick allows you to perform a calculation instead of 2! The opposite of one percent is 100% minus the percentage you work with, that is, the amount of items you still pay for. If you want to buy a shirt that is 30% off, the opposite of this is 70%, which means you have to pay 70% of the original price. [11]
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    3. Convert the opposite percentage to one decimal place. To convert one percent to one decimal place, divide by 100%, multiply by 0.01 or move the two decimals to the left . In this example 70% / 100% = 70/100 = 7/10 = 0.7. [12]
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    4. Multiply the original price by the new decimal. If the shirt you want is $ 20, multiply $ 20 by 0.7. This comes to $ 14, which means that the shirt is now on sale for $ 14. [13]
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    5. Calculate your savings afterwards to feel better. Once you get home, it may be a good idea to check your receipts, not only to make sure the discounts were applied correctly but to see how much you have saved completely. Here you can simply subtract the selling price from the original price ($ 20 – $ 14 = $ 6 saved)!
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    [ Edit ] Video [19659051] [ Edit ] Tip

    • x% of y is the same as y% of x. For example, 10% of 30 = 3 = 30% of 10. [14]

    [ Edit ] Help to calculate percentage

    WH.shared.addScrollLoadItem ( & # 39; 5f15bf81e4712 & # 39;) Convert Decimal to Percent Cheat Sheet
    WH.shared.addScrollLoadItem (& # 39; 5f15bf81e53ae & # 39;) Convert Fraction to Percent Cheat Sheet [1965905] Edit ] Related wikiHows

    • Work With Percentages
    • Working with percentages of increase and decrease
    • Convert percentages, fractions and decimals
    • Work out a fraction of an amount

    Edit ] References

    Edit ] Quick Overview

    1. https://www.dummies.com/education/math/basic-math / how-to-calculate-percentages /
    2. https://www.dummies.com/education/math/basic-math/how-to-calculate-percentages/
    3. https : //www.dummies.com/education/math/ basic mathematics / how to calculate percentages /
    4. https://www.dummies.com/education/math/basic-math/how-to- calculate-percentages / ?? 19659074vard ↑ https://www.dummies.com/education/math/basic-math / how to calculate percentages /
    5. https://www.dummies.com / education / math / basic-math / how-to-calculate-percentages /
    6. https: //www.mathsisfun.com/percentage-calculator.html
    7. https: // www.mathsisfun.com/percentage-calculator.html
    8. https: //www.mathsisfun .com / percent-calculator.html
    9. https://www.mathgoodies.com/ lessons / percent / sale_price
    10. https://www.mathgoodies.com/lessons/percent / sale_price
    11. https: // www. mathgoodies.com/lessons/percent/sale_price
    12. https://www.mathgoodies.com/lessons/percent/sale_price
    13. https://www.mathsisfun.com/percentage- calculator.html

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