Mathematics Stack Exchange
Mathematics Stack Exchange

Questions tagged [ratio]

For questions concerning the ratio of a certain quantity to another.

In mathematics, a ratio is a relationship between two quantities indicating how many times the first number contains the second. For example, if a bowl of fruit contains eight oranges and six lemons, then the ratio of oranges to lemons is eight to six (that is, $8:6$, which is equivalent to the ratio $4:3$). The numbers compared in a ratio can be any quantities of a comparable kind, such as objects, persons, lengths, or spoonfuls. A ratio is written "$a$ to $b$" or $a:b$, or sometimes expressed arithmetically as a quotient of the two.

1100 questions
0
votes
1 answer

finding the ratio when two other ratios are given

The ratio of incomes of a and b is 3:4 and ratio of their expenditure is 4:5 . what can be their possible ratio of savings 9:10 or 3:4 or 4:5 or 13:20. I don't find anything suitable in the options I think the answer is 2:3 but it has…
tapadia newlon
  • 77
0
votes
1 answer

Need help with ratio calculation

I have 2 objects with the width of: Object 1 = 375 Object 2 = 359 If I change Object 1 width to 333.5, what would object 2 be? This is probably really simple, but I'm trying to get the answer to be 311. Please explain answer. Thanks!
Steve
  • 103
0
votes
2 answers

Inverse of ratio

Say I have two equations: $$a = {b \over c} \\ d = {c \over b}$$ Now assume that I know the value of $b \over c$ (e.g. $4$), how would I then determine the value of $c \over b$? Note: I do not require the values of $b$ and $c$, just their ratio…
Firetramp
  • 29
0
votes
3 answers

Inverse proportion - Word Problem

Question: given that $B^2$ is inversely proportional to $A+3$ and $B$ is always positive, find the value of $B$ when $A=17$ if $B=5$ when $A=2$. I am so confused on how to work out this question. I know this is a pretty easy question to all of you.…
user215301
  • 3
0
votes
1 answer

Comparing ratios?

Im 12 and in need help on how to do these comparing stuff. Here is my problem/question So how do I figure this out?
Plates...
  • 27
0
votes
2 answers

Ratios with Ages

The ratio of Sam's age to his son John's age is 8:3. If the sum of their ages is 55 years, what is the age difference between John and his dad in years? So, I divided 55 by 11 and got 5, then multiplied that by 8 to get Sam's age (40), then the…
John
  • 159
0
votes
1 answer

Ratio of downstream and upstream velocity

A boat first travels downstream for $21$ km then it turns the opposite direction and travels upstream for $4$ km. It repeats again but now it travels downstream for $12$ km then travels upstream for $7$ km. The time it takes for the first travel and…
user71346
  • 4,171
0
votes
1 answer

query on shares

A person bought a share (par value is rs 50) at the rate 150 from market. If it gives20% dividend what is effective return?
honey
  • 1
-1
votes
1 answer

Fuel and Oil Ratio Problem

Joel mixes petrol and oil in the ratio 40:1 to make fuel for his leaf blower. (i) He pours 5 litres of petrol into an empty container to make fuel for his leaf blower. How much oil should be added to the petrol to ensure that the fuel is in the…
Caz
  • 1
-1
votes
1 answer

Mixture of wine and water

I'm new here, so kindly bear with me if this question is too trivial for the forum. I tried working it out but to no avail. A solution contain wine and water in ratio 2:1. Out of it 36 litre solution is replaced by 15 litre water. Again 26 litre…
user1293052
-1
votes
1 answer

Get values for 2 desired ratios

I'm not really a maths guy, apologies if this is either trivial or impossible If I have 2 formulas, say (ax + cxy) / (ax + b + cxy + d) = r and (cxy + dy) / (ax + b + cxy + d) = s and I need to find both x and y, how would I go about this, can it be…
gubitza
  • 1
-1
votes
1 answer

Find the height of a person caught on a CCTV camera

A CCTV camera was installed on the roadside. A suspected person was caught on the CCTV doing something illegal. The height of the person in CCTV footage/monitor is 4 cm. The CCTV camera was installed at a distance of 17 meters from the suspected…
Sann
  • 63
-1
votes
2 answers

If $ a \propto b $ and $ b \propto \sqrt{c} $, then is $ a \propto \sqrt{c} $?

I'm sorry for asking a really simple question, but I just wanted to make sure.. If $ a \propto b $ and $ b \propto \sqrt{c} $, then is $ a \propto \sqrt{c} $ ? I think this is true, because if I increase $c$ by factor of $9$, $b$ will increase by a…
Freddie
  • 461
-1
votes
1 answer

in search of a Formula for ratio where one element is 0

Very nice to meet you all. I am searching to find the value x for the given image. its a ratio that looks like this: 0: 1 = 350 : Y but this leads if we solve for Y: 0 * Y = 350 * 1 Y = 350/0 which is undefined. How can i get the Y value in such…
j2emanue
  • 109
-1
votes
1 answer

Ratio and the equality of money

Bernice and Lily have some money. If Bernice gives Lily \$120, they will have an equal amount of money. If Lily gives Bernice \$120, the ratio of the amount of Bernice's money to the amount of Lily's money will become 4:1. How much money does each…
user31659
  • 1
1 2 3
…
16 17