A percentage is a number or ratio expressed as a fraction of $100$. It is often denoted using the percent sign, "$%$", or the abbreviation "$\mathrm{pct}$." -Wikipedia. Percentages are used when describing portions or proportional changes.
Questions tagged [percentages]
1440 questions
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Percentual increase when the old Value is zero
How do I compute the increase when the old value is zero? I know that usually we compute it as
$$
\frac{N-V}{V} \times 100,
$$
where $N$ is the new value and $V$ is the old value.
So,
going from $50$ to $500$, the increase is $900\% =…
Lucas Vendramini
- 121
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2 answers
How to use a single value to map to multiple percentages?
I am a programmer so please bear with me!
I am given a percent, represented by a value of 0-1. I want to map evenly spaced percents where I know the total amount of areas and the index of the area I'd like to reference.
For example, given 0.5 and…
nissy
- 21
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which of the expression shows the change in the effective rate on the bank account if the Interest is compounded monthly than quarterly?
$(1+0.09/n)^n -1$ , the expression gives the effective annual interest rate on a bank account that pays an annual interest rate of $9\%$ , compounded $n$ times per year. Which of the following expressions, shows the change in the effective rate on…
user711349
- 11
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1 answer
How do you scale percentages of different numbers?
this is something that’s stumped me for a while once I realized that the way I was doing it was giving me the wrong answer and, in hindsight, didn’t make sense.
Let me give you a scenario: In a random country X (let’s call it Mathland), Group A is…
Fahim Azaz
- 11
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2 answers
I 'reverse engineered' a problem about percents but need help understanding it.
Tapiwa raked 5% more leaves than Adam raked. Tapiwa raked 357 liters of leaves
How many liters of leaves did Adam rake?
It is a question on one of my homework problems about percentages. I had no idea where to start from so I began by getting 5%…
Brucc
- 117
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3 answers
Calculate percentage in an irregular Slider
Het guys,
Let's say we have a slider like this
As you can see the slider have irregular Steps positions, so I managed to draw the steps like this 0% 33.33% 66.66% 100%.
My question is how can i calculate the correct percentage of the value (200…
Diptox
- 115
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2 answers
Why is measuring percent change (or Year over year change) of percents bad?
So I'm calculating female representation of our workforce and trying to track changes over time. So say in Jan 2018 I had 40% of the workforce are females and in Jan 2019 I had 45%. The percent change is 12.5%. I'm getting push back on this because…
Ted Mosby
- 113
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1 answer
Calculate total percent change from incremental changes
Is there a formula to calculate a total percent change of a value from multiple changes?
Example:
Initial: 100
-10%: 90
+5%: 94.5
-20%: 75.6
So I am looking for some formulaic way of taking the initial value of 100 and the changes of -10%,+5%, and…
The Nightman
- 171
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2 answers
What does the relationship between dividing percentages signify in this problem?
The following is an example calculation from Wikipedia's page on Percentage:
I understand everything up to the point where 3% is divided by 10%. I cannot seem to understand why these two percentages are divided, why do we divide? I understand how…
Sphygmomanometer
- 231
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Split up bonus inversely to errors
I have five teams, A-E, who have made errors as follows (errors are percentages):
A 30
B 20
C 12
D 22
E 16
I have to allocate a bonus of $50 in inverse proportion to their errors.
I initially tried a naive approach to allocate based on…
Jeremy
- 11
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0 answers
Percentage chance of bringing home a raffle prize
So I bought 3 tickets for a raffle and 100 tickets were sold. Once tickets are taken out they are not returned to the pot to win again. There are 40 prizes total. What are the odds that I win 1 prize out of the 40 and what are the odds that all 3 of…
Griepp06
- 11
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2 answers
How to get the reverse percentage (not amount of reverse percentage)?
if 100 x 1.17 (17%) = 117, how can I know how many % I have to deduct 117 to get 100? Obviously, this is no more 17%.
The same can be applied if 100 - 10% = 90. Then how many % I have to add to 90 to get 100? Again, it is no more 10%.
I know how…
mathco
- 115
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1 answer
Average percentage of a subcategory
I have a list of numbers of unknown length whose average is x (in fact its 68, but that's not relevant). Some subcategory of that list has an average of y (71) - I don't know how many items are in the subcategory nor what percentage of the list is…
MrB
- 115
- 4
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What is the correct terminology to be used when talking about % changes?
Throughout my life, I read a "60% increase in x" as $ 60\% * x + x $. For example, if a question asked, "If the initial value of Gold was $39, 162 and if it increased by 50%, what is the price now?", I'd add 50% of 39,162 to get 58, 743.
Now, if I…
WorldGov
- 947
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1 answer
How to add percentage value by multiplication?
I'm studying the APL language and doing the exercises here: One of the questions is:
b) Add 15% to each number in the list 14 5 78 145.
I tried this:
14 5 78 145 + (14 × 15 ÷ 100) (5 × 15 ÷ 100) (78 × 15 ÷ 100) (145 × 15 ÷ 100)
I get the correct…
zeynel
- 365