Can someone explain this maths questions and how you work it out?
2/3 plus 1/4 plus 3/6. The answer is 17/12 but how do you work it out? Can someone please explain it to me step by step?
31-35, F
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Mordi · 31-35, M
I didn't take a lot of math in English so I'm not sure about the terms here.
You need a common denominator to add them. So you need to make the lower number the same for each one by multiplying them accordingly.
4)2/3 = 8/12.
3)1/4 = 3/12.
2)3/6 = 6/12.
And then you can just add all the top parts together.
8/12 + 3/12 + 6/12 = 17/12 = 1 5/12.
You need a common denominator to add them. So you need to make the lower number the same for each one by multiplying them accordingly.
4)2/3 = 8/12.
3)1/4 = 3/12.
2)3/6 = 6/12.
And then you can just add all the top parts together.
8/12 + 3/12 + 6/12 = 17/12 = 1 5/12.
summerlove · 31-35, F
@Mordi Can you explain it more simpler? I still don't get it lol.
Mordi · 31-35, M
Hmmmm...I can try another example.
When you multiply both the top and the bottom the number is always the same value.
2)1/2 = 2/4
3)1/2 = 3/6
4)1/2 = 4/8
5)1/2 = 5/10
These are all a half. To add fractions together, you need the bottom number to be the same, otherwise you just can't do it. But with fractions, you can multiply the top and bottom, and in this way change the bottom number without it affecting the value.
So if you wanted to add 1/2 and 2/3, you'd need to first change the bottom numbers. The easiest way to find a number that would work is just to multiply the bottom numbers of each number together. In this case you take the 2*3 = 6. So now we know if we make the bottom number 6, we can add them together. The way we make 1/2 have a bottom number of 6, you figure out how many times 2 goes into 6 = 6/2 = 3. So you have to multiply the top and bottom with 3.
3)1/2 = (1*3)/(2*3) = 3/6
Then you'd need to make the 2/3 have a bottom number of 6. So figure out how many times 3 goes to 6 = 6/3 = 2. Now we now we have to multiply the top and bottom with 2.
2)2/3 = (2*2)/(3*2) = 4/6
Now that we have two fractions with the same bottom number, we can just add the tops together.
3/6 + 4/6 = (3+4)/6 = 7/6
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In your case there are 3 different numbers so it can be more difficult to find the same bottom number. But you can actually do it the exact same way.
2/3, 1/4, 3/6.
Now just multiply the bottom numbers together. 3 * 4 * 6 = 72. The problem with this would be that you'd have to multiply with big numbers and people usually don't want to do that. So it's better to find a number that all 3, 4 and 6 go into evenly. So you need to go through the multiplication table of each number.
3 6 9 12 15 18 21 24 27 30
4 8 12 16 20 24 28 32 36 40
6 12 18 24 30 36 42 48 54 60
Now you just need to find the smallest number they all have in common! It's clearly 12. So the easiest way to solve your problem is by using 12. Because 12 is in all of their multiplication table. But how do you get 12 to be the bottom number for all of them? You need to find out what to multiply them with!
2/3 -> 12/3 = 4
1/4 -> 12/4 = 3
3/6 -> 12/6 = 2
Now we have the numbers we need to multiply the top and bottom of the fractions with. So now we use those numbers to turn all of our fractions into fractions with 12 on the bottom.
4)2/3 = (2*4)/(3*4) = 8/12
3)1/4 = (1*3)/(4*3) = 3/12
2)3/6 = (3*2)/(6*2) = 6/12
Now you just add the top numbers together.
8/12 + 3/12 + 6/12 = (8+3+6)/12 = 17/12
When you multiply both the top and the bottom the number is always the same value.
2)1/2 = 2/4
3)1/2 = 3/6
4)1/2 = 4/8
5)1/2 = 5/10
These are all a half. To add fractions together, you need the bottom number to be the same, otherwise you just can't do it. But with fractions, you can multiply the top and bottom, and in this way change the bottom number without it affecting the value.
So if you wanted to add 1/2 and 2/3, you'd need to first change the bottom numbers. The easiest way to find a number that would work is just to multiply the bottom numbers of each number together. In this case you take the 2*3 = 6. So now we know if we make the bottom number 6, we can add them together. The way we make 1/2 have a bottom number of 6, you figure out how many times 2 goes into 6 = 6/2 = 3. So you have to multiply the top and bottom with 3.
3)1/2 = (1*3)/(2*3) = 3/6
Then you'd need to make the 2/3 have a bottom number of 6. So figure out how many times 3 goes to 6 = 6/3 = 2. Now we now we have to multiply the top and bottom with 2.
2)2/3 = (2*2)/(3*2) = 4/6
Now that we have two fractions with the same bottom number, we can just add the tops together.
3/6 + 4/6 = (3+4)/6 = 7/6
[sep][sep][sep][sep][sep][sep][sep][sep][sep]
In your case there are 3 different numbers so it can be more difficult to find the same bottom number. But you can actually do it the exact same way.
2/3, 1/4, 3/6.
Now just multiply the bottom numbers together. 3 * 4 * 6 = 72. The problem with this would be that you'd have to multiply with big numbers and people usually don't want to do that. So it's better to find a number that all 3, 4 and 6 go into evenly. So you need to go through the multiplication table of each number.
3 6 9 12 15 18 21 24 27 30
4 8 12 16 20 24 28 32 36 40
6 12 18 24 30 36 42 48 54 60
Now you just need to find the smallest number they all have in common! It's clearly 12. So the easiest way to solve your problem is by using 12. Because 12 is in all of their multiplication table. But how do you get 12 to be the bottom number for all of them? You need to find out what to multiply them with!
2/3 -> 12/3 = 4
1/4 -> 12/4 = 3
3/6 -> 12/6 = 2
Now we have the numbers we need to multiply the top and bottom of the fractions with. So now we use those numbers to turn all of our fractions into fractions with 12 on the bottom.
4)2/3 = (2*4)/(3*4) = 8/12
3)1/4 = (1*3)/(4*3) = 3/12
2)3/6 = (3*2)/(6*2) = 6/12
Now you just add the top numbers together.
8/12 + 3/12 + 6/12 = (8+3+6)/12 = 17/12