How to Work With Percentages
The first thing to understand is that there aretwo major categoriesof percentage problems:straight comparison questions(such as, "35 is 5% of what number?") andincrease/decrease questions(like, "if a blouse that cost originally is on sale at 20% off, what is the new price?). The increase/ decrease kind are complicated enough to require a separate Wikihow article, so let's focus on just the straight comparison for right now.
The other thing to know is that there are two major approaches to these questions. One is based on an equation involving decimals, and the other relies on proportions. I'm going to stick with the method that's based on the decimal equation, which is:% x (whole amount) = (partial amount). This equation can be rearranged like this:% = (partial amt) / (whole amt). It can also be written like this:(whole amt) = (partial amt) / %. Which arrangement you need depends on which kind of problem you have.
The Place to Start
Your first task is tofigure out what kind of problem is in front of you.In a straight comparison situation, there arethree stylesof problems. Thefirst style is the "no percent" question. Those would sound like: "what percent of 25 is 16?" or "8 is what percent of 32?". Thesecond style is the "no entire amount" question. Those would be phrased like: "15 is 6% of what number?" or "78% of what number is 20?". Thethird style is the "no partial amount" question, which would sound like: "What is 52% of 49?" or "14% of 225 is how much?"
Solving an "Unknown Percent" Question
If you do not see a number marked by a % (or possibly the word "percent"), then this is almost certainly the "no percent" type of question.
Decide which of the other numbers is the "whole amount" and which is the "partial amount".For example, a problem that says "8 is what percent of 32?" indicates that the 32 is the whole amount and the 8 is the partial.What tips this off:the 8 connects directly to the "is", while the 32 connects directly to the "of".
Use the equation% = (partial)/(whole).So on the calculator, punch in the partial amount, hit divide, enter the whole, and hit equals.
This will give you a decimal, which you convert into a percentage by moving the decimal point two places to the right.
- Example: "8 is what percent of 32?". Take 8, divide by 32, hit equals; get 0.25; convert that to 25%.
- Example: "what percent of 25 is 16?". Enter 16, divide by 25, hit equals; get 0.64; convert to 64%.
- Example: "what percent of 12 is 45?". Enter 45, divide by 12, hit equals; get 3.75; convert to 375%. (Answers larger than 100%, while rare, are acceptable).
- Example: "9 is what percent of 250?". Enter 9, divide by 250, hit equals; get 0.036; convert to 3.6%.
Solving an "Unknown Entire Amount" Problem
Let's say you have a percent. You now need to decide if the question is the "no whole amount" style or the "unknown partial amount" style. This is a trickier call to make and much depends on the context of the question.
Look for the markers "is" and "of" and "what"."Is" tends to be associated with the partial amount, while "of" is paired with the entire amount. The word "what" indicates the unknown.
- Example: A question says, "what is 10% of 16?" The phrase "what is" indicates that the partial amount is unknown. The phrase "of 16" indicates that 16 is the whole amount. This is an "unknown partial amount" problem.
- Example: A question says, "15 is 25% of what number?" The phrase "of what" means that the entire amount is unknown, but the phrase "15 is" shows that 15 is the partial amount. This would be an "unknown entire amount" problem.
Let's assume you have an "unknown entire amount" problem, like "15 is 25% of what number?". First of all, change the percent into a decimal --- 0.25 instead of 25%, 1.38 instead of 138%, 0.07 instead of 7%, etc.
Use the equation:(whole amt) = (partial) / %.
Using your calculator, enter the partial amount, hit divide, enter the percentage decimal, and hit equals.
- Example: "15 is 25% of what number?". Grab your calculator, enter 15, hit the divide key, enter 0.25, hit equals. The answer is 60. You're done. (Notice, it's just 60. Not 60%.)
- Example: "32% of what number is 16?". Enter 16, hit divide, enter 0.32, hit equals; the answer is 50.
- Example: "125% of what number is 80?". Enter 80, hit divide, enter 1.25, hit equals; the answer is 64.
- Example: "6 is 7.5% of what number?". Enter 6, hit divide, enter .075, hit equals; the answer is 80.
Solving an "Unknown Partial Amount" Problem
Look for the "is", "of", and "what" (or possibly "how much").If the "is" and the "what" are closely associated, like in the question "what is 10% of 16?", then you have a "no partial amount" problem.
Here's what to do:Change the percentage back to a decimal, so 32% is 0.32 and 75% is 0.75 and 150% is 1.5 and 6% is 0.06, and so forth.
Use the equation:% x (whole amt) = (partial amt). In other words, you multiply the percent with the entire amount.
- Example: "what is 10% of 16?". Enter 0.10, hit multiply, enter 16, hit equals. The answer is 1.6 (notice, no % sign on the answer).
- Example: "230% of 40 is what?". Enter 2.3, hit multiply, enter 40, hit equals. The answer: 92.
- Example: "how much is 37% of 200?". Enter 0.37, hit multiply, enter 200, hit equals. Answer: 74.
QuestionIf a number is increased from 32 to 64, what is the percentage increase?Top AnswererFirst find the increase, which is 64 - 32 = 32. Then divide the original number into the increase. That gives you a decimal number, which you would multiply by 100 to get a percentage. In this case, dividing 32 into 32 gives you 1, which when multiplied by 100 gives you 100%. In this specific case, the original number is half the final number, which means the increase was 100% (i.e., the original number was doubled).Thanks!
QuestionWhat is 1 percent of 833244.48?Top AnswererAnytime you multiply by 1%, keep the same numbers and just move the decimal point two spaces to the left.Thanks!
QuestionWhat is 1.5% of 55460?wikiHow ContributorCommunity AnswerMultiply 55,460 by 0.015.Thanks!
QuestionWhat percent of 16 is 12?wikiHow ContributorCommunity AnswerIn fraction form, with 12 as the numerator (top) and 16 as the denominator (bottom), simplify that fraction. In which case, 12/16 = 6/8 = 3/4. 3/4 times 100 equals 75%, and there's your answer.Thanks!
QuestionWhat percentage of 232 is 200?Top AnswererDivide 232 into 200. That gives you a decimal number, which you then multiply by 100 to get a percentage.Thanks!
QuestionWhat is 20 percent of .50?wikiHow ContributorCommunity AnswerTo figure out this percentage, you must find 20 percent of 1 and multiply it by 8.50. The equation will be 0.20 x 8.50 = 1.7. Thus, your answer is .70.Thanks!
QuestionIf 3,509,541 is 78%, what is its 100%?Top AnswererSet up a ratio: 3,509,541 is to x as 78 is to 100. (3,509,541 / x = 78 / 100). Solve for x (the number you're looking for), by cross-multiplying: (3,509,541) (100) = (78) (x).Thanks!
QuestionWhat is the percent decrease of 126 alarms per patient in 12 hours to 4 alarms per patient in 4 hours?Top AnswererIt's a 90.5% decrease. The way you calculate it is this: To compare the two situations accurately, consider 4 alarms in 4 hours to be the equivalent of 12 alarms in 12 hours (averaging one per hour). The difference between 126 and 12 is 114. 114 ÷ 126 = 0.9047, rounded to 0.905 = 90.5%.Thanks!
QuestionIf I have 3% of material A that goes into a Material B which makes up 32% of the end product, what is the overall percentage of material A in the end product?Top AnswererMultiply 32% by 3%: (.32)(.03) = 0.0096 = 0.96%.Thanks!
Question3 people out of a total of 3,026 had an auto accident in the last 10 years. What is the estimate of the percentage of people who had an auto accident?Top AnswererA good estimate would be 0.1%. However, there's no need to estimate. Just divide 3 by 3,026 to get the exact percentage: 3 ÷ 3,026 = 0.00099, which is 0.099%.Thanks!
How to work with percentages on Excel for accounting?
To work with percentages, start by identifying what type of problem you’re working with. For example, if you see the words “is,” “of,” and “what,” you’re likely trying to solve for an unknown entire amount. If the question asks “15 is 25% of what number?” first change the percent into a decimal, which means moving the decimal point two places to the left, of .25. Now, if you want to use a calculator, enter 15, hit the divide key, enter .25, hit the equals key, and you get 60.
- To summarize, you either: A) divide the partialBYthe whole; or, B) you divide the partialBYthe percent; or, C) you multiply the whole by the percent. Which one you use depends on which numbers you have.
- Apply the TLAR --- That Looks About Right --- principle. Make sure that your answer is reasonable.
- With the "no partial amount" style of problem, the order of the multiplication does not matter. You could solve "230% of 45" with the sequence 2.3 x 45 = or with 45 x 2.3 =
- The only time you multiply is if you have the % and the whole amount.Otherwise, you're dividing.
- The order of division is vitally important!In both of the kinds of questions that are solved with division, thepartial amount goes into the calculator first.
- Most calculators have a percent key. Its purpose is to move the decimal point twice to the left, turning 35% into 0.35, and 325% into 3.25, and 6% into 0.06, and so on. I adviseAGAINSTusing this key because I find that most of my students move the decimal point themselves, then hit the % key as well, and everything gets screwed up.
Video: Math Antics - What Are Percentages?
Beats Solo – Designed For Sound. Tuned For Emotion
Prom Pretty: The Best Makeup Palettes For Your BigNight
From Beard Oil to Body Scrubs– These Are The Best Beauty Gifts for Men
Becaplermin Topical Reviews
How to Treat and Heal Sunburned Skin
The 8 Most Important Things I Learned From My Fathers Infidelity
Alternative Therapies for Back Pain
Watch Kerrys remarks
Know Your Fat Danger Zones
OK, There’s Something Seriously Wrong with This Photoshopped Vogue’ Cover
And Then I Got Lost But Knew Exactly Where I Was
How to Drink Matcha Green Tea
How to Dress up Jeans: 11 Ways to Make Your Denim StandOut
How to grow taller after puberty – Tips