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May 3rd, 2018, 08:02 AM   #1
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When should I add ratios in denominator?

Sometimes we add ratios in denominator like:

a: b = 4: 1

a + b = 14

To know how much A is more than B then we add ratios in the denominator: 14 × 3/5 = 42/5 = 8.4%

Sometimes we won't add ratios in denominator:

X : Z = 13 : 9

X is 182.

Then Z = 182 × 9/13 = 126 (here we didn't add ratios in denominator)

When should I add ratios in denominator?
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May 3rd, 2018, 09:02 AM   #2
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Quote:
Originally Posted by Ganesh Ujwal View Post
Sometimes we add ratios in denominator like:
a: b = 4: 1
a + b = 14

To know how much A is more than B then we add ratios in the denominator: 14 × 3/5 = 42/5 = 8.4%
Since we have a:b = 4:1, then a is clearly 300% more than b, NOT 8.4%
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May 3rd, 2018, 09:08 AM   #3
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Quote:
Originally Posted by Denis View Post
Since we have a:b = 4:1, then a is clearly 300% more than b, NOT 8.4%
Sorry, my question is different.
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May 3rd, 2018, 09:30 AM   #4
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Well then, you're too smart for me...
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May 3rd, 2018, 10:09 AM   #5
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Quote:
Originally Posted by Ganesh Ujwal View Post
Sometimes we add ratios in denominator like:

a: b = 4: 1

a + b = 14

To know how much A is more than B then we add ratios in the denominator: 14 × 3/5 = 42/5 = 8.4%
You use lower case letters in the statement of the hypotheses and capital letters in the sentence that you are confused on. In addition, the number 3/5 seems to have come out of nowhere.

It isn't that your question is different. It is that you cannot properly formulate a question without clouding it with obfuscation.
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May 3rd, 2018, 12:50 PM   #6
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Saying a:b= 4:1 is the same as saying $\frac{a}{b}= \frac{4}{1}$ ad both are the same as saying that a=4b. Adding the condition that a+ b= 14 we have 4b+ b= 5b= 14 so b= 14/5 and a= 14- 14/5= 56/5. a is 56/5- 14/5= 42/5 more than b. That is. a is (42/5)/(14/5)= 42/14= 3 times or 300% "more than b". If that is NOT the question you are asking please tell us what the question is!
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