Questions tagged [percentages]

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.

1440 questions
1
vote
1 answer

I need a mathematical percentage for a final exam grade, too see how many points I need for a $90\%$ average.

I have a math exam tomorrow. My current overall-average is $98\%$(A). The exam will be $15$ OR $20\%$ of the final grade. What percentage would I need on this exam to get at least $90\%$ (A-) as a final year grade? The calculation I think for $20\%$…
Michael
  • 27
1
vote
1 answer

What percentage do I need to pass my exam?

I have to get 60% to pass my course. It is split between gradings of: 10% for participation; 30% for essay; 60% for exam. I have so far recieved 50/100 for my participation - so 50% 30/100 for my essay - 30% and am yet to sit my exam. What do I need…
1
vote
0 answers

Percentage share question?

Three Business partners share a business in the following percentages. Person 1 = $40$% Person 2 = $30$% Person 3 = $30$% Then p1 and p2 agreed to became $50-50$ on the business by purchasing the share of p3. the business was valued at…
maxy
  • 11
1
vote
3 answers

A man spends 80% of his income. If his income is increased by 40% and expenditure is increased by 10%, by what percentage is savings increased?

Actual Answer is $160\%$. What I have done: I took his income as $100$. According to the question, his income is increased by $40$ so, $140$. According to the question, his expenditure is $80$, then his expenditure increased by $10\%$ so…
1
vote
2 answers

Percentage of a number

How can we find out what percentage 2 gigabytes is of 15 gigabytes? I am not calculating correctly: 2 gb * x (percentage) = 15 gb x = 15/2
1
vote
0 answers

Percent variance - negative and positive numbers

I need to calculate the percent variance between a negative and positive number and am not sure how to do it. The numbers are $-45000000$ and $8500000$. Normally when I look at percent variance I would do the following,…
1
vote
1 answer

Differences between two models

Vladimir bought a car for $250000$ USD. He has two models to describe the car's loss of value. Model 1: $y=250000-25000x$. Model 2: $y=250000 \cdot 0.8^x$ where $y$ is the cost and $x$ is the amount of years that have passed since the purchase.…
1
vote
2 answers

General formula - % of %

I would like to find a way to represent the following idea in a general formula: I have 100%, then I subtract 2% from it. Now I have 98% of the original value and subtract 4% from it, which leaves me with 94.08%. Basically, it is something…
Th3B0Y
  • 111
1
vote
1 answer

Quick way to express percent from negative interval

I have some data which looks like this: I get a number in the -6/+4 range and I need to express it with percent. If I get 4 of course the result is 100%, If I get -6 is 0%, etc. Is there a quick formula I can use to obtain the percent value of, say,…
JessyP
  • 13
1
vote
1 answer

Percentages and Concentrations

What is the concentration of a sugar solution made by mixing 1 kilogram of 12% sugar solution with 2 kilograms of water. Sorry about the title, I'm not sure what to call this. I'm really not sure where to start. So 12/100 + 200%? 12/300 = 6/150 =…
John
  • 159
1
vote
5 answers

Proportions with Percentages

How would I solve this using a proportion? What is $2$% of $\frac{1}{2}$? I tried doing $\frac{2}{100} = \frac{x}{50}$, but I'm not sure if its right.
John
  • 159
1
vote
2 answers

10% of ten English pounds £

I, unfortunately, have serious dyscalculia and struggle with maths. This makes figuring out simple everyday maths quite difficult. I'd really appreciate the help with this. Thanks in advance.
1
vote
1 answer

Percentage increase of two percentages

Can anyone help me with this problem? What is the percentage increase from 27.7% to 28.2%? I came up with 1.8% but my brother keeps telling me it's 18%
Timmy
  • 11
0
votes
2 answers

Profit and loss problem

A shopkeeper allows a discount of 12.5% on the marked price of a certain article and makes a profit of 20%. If the article costs the shopkeeper Rs 210, then the marked price of the article will be?
Vikash
  • 47
0
votes
1 answer

Why the answer is not negative here?

If one number is $80\%$ of the other and $4$ times the sum of their squares is $656$, then What are the numbers? My answer is - let the two numbers be x and y. $x = \frac 45 y$ $4(x^2 + y^2) = 656$ $\implies x^2 + y^2 = 164$ Now substitute $x…
dexterous
  • 621