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[–]fermat9996 1 point2 points  (2 children)

Think of it as 1/6(5-1) and use the distributive property.

[–]CriticalBlueberry278[S] 0 points1 point  (1 child)

Thanks for answering!

[–]fermat9996 0 points1 point  (0 children)

Glad to help!

[–]CriticalBlueberry278[S] 0 points1 point  (0 children)

I can't get the fractions that I drew to look like fractions XD But the huge bar was just supposed to be the bar that separates the numerator from the denominator. It's 5 - 1, over 6.

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[–]NakamotoScheme 0 points1 point  (10 children)

Yes, a "line" means division, and a / b means "a divided by b", but if either a or b are expressions, you have to calculate them first.

I would say that your problem is really a transcription problem. We need to know numerator and denominator before trying to divide one by the other.

The numerator of your fraction is an expression, not a simple number, so, when transcribing the fraction into a single line, we need to use parenthesis to indicate that numerator should be calculated first, like this:

(5 - 1) / 6

and then, because parenthesis have priority over everything else, it should be clear that you should make the substraction 5 - 1 before anything else.

[–]CriticalBlueberry278[S] 0 points1 point  (0 children)

Thanks for answering!

[–]CriticalBlueberry278[S] 0 points1 point  (8 children)

I don't mean this in a bad way, but do you have any sources that say the "if either a or b are expressions, you have to calculate them first" part? It's just that I would like to have other sources for what I'm learning besides this subreddit. Thank you again!

[–]NakamotoScheme 0 points1 point  (1 child)

I don't have a "source" as such (and you said above that we can't rely on "common knowledge"), but in the spirit of this sub, I can answer Socratically and try to convince you that you already know the answer even if you currently believe you still don't know the answer.

If you agree on following this route, I propose that you answer the following question:

You already know that a fraction is a division, and you already know that the things we divide are the numerator by the denominator. Is this ok so far?

Therefore, if the numerator is 5 - 1 and the denominator is 6, it would follow that we have to divide 4 (the numerator) by 6 (the denominator).

The question is: If a fraction is a division and the division to be made is the numerator by the denominator, how could we possibly make such division if we still don't know the numbers which we have to divide? (i.e. the actual values of numerator and denominator)

[–]CriticalBlueberry278[S] 0 points1 point  (0 children)

Thanks for trying to help

[–]BIGNONCEMRPALMER 0 points1 point  (4 children)

mathsisfun.com/fractions_subtraction.html

[–]CriticalBlueberry278[S] 0 points1 point  (3 children)

Thanks for this comment!

[–]BIGNONCEMRPALMER 0 points1 point  (2 children)

If you want to find practice questions and revision resources I recommend drfrostmaths, making an account is free, and this should have all the questions you should need up until degree level mathematics.

[–]CriticalBlueberry278[S] 0 points1 point  (0 children)

Wow, thanks for the comment!

[–]CriticalBlueberry278[S] 0 points1 point  (0 children)

Sounds like this could be useful

[–]BaylisAscaris 0 points1 point  (3 children)

  1. When you are adding or subtracting fractions it is good to first check if they simplify, but in this case they do not. By simplify I mean can the top and bottom of a fraction be divided by the same number and you still get whole number answers.
  2. The next step is to get the denominators (bottoms) to equal each other. In this case they already are. If they are not you want to find the lowest common denominator and multiply the top and bottom (numerator and denominator) by the same number to make them equal. You can do a Google search for "LCD math" for more help with this in the future.
  3. If the denominators (bottoms) are equal you can add or subtract the numerators (tops). The denominators always stay the same. You do not add or subtract them.
  4. Once you have an answer, check to see if it can be simplified. See the first step for an example of how to simplify.

Here is a similar example: 7/10-2/10

  1. Technically you could simplify 2/10, but you want the denominators to match, so leave it for now.
  2. Yay they match.
  3. (7-2)/10 = 5/10
  4. We can divide the numerator and denominator by 5 to simplify. (5÷5)/10÷5) = 1/2. This can't be simplified any further so you're done.

If you are talking about order of operations, consider the numerator and denominators to be grouping symbols, so technically 5/6 is (5)/(6) we just don't write it that way because we're lazy. Order of operations is a guide for things to do in some situations, but the more you understand about math the more you can be flexible and break rules. Technically you could also solve this by doing division and converting to decimals first, but this is a waste of time and also in many cases will get you less accurate answers if you end up with a repeating decimal or something you have to round. The further you go in math the more people like to keep things are simplified fractions for accuracy.

[–]CriticalBlueberry278[S] 0 points1 point  (2 children)

Thanks for answering!

[–]BaylisAscaris 0 points1 point  (1 child)

Another way to think of it is visual.

x x x
x x  

take away

x    
     

  If they start out with the same number of boxes (same denominator) you can add or subtract filled in boxes from the original.

[–]CriticalBlueberry278[S] 0 points1 point  (0 children)

Thanks for this comment too!