How do you add negative Numbers, fractions and decimals?

Answer 1

Adding negative numbers:
You could rewrite something like (-3)+(-5) as (-1*3)+(-1*5). You can rewrite this as -1*(3+5), equal to -8.

Adding fractions:
Find the least common multiple of the denominators. Alter the fractions (multiply the numerator and denominator by a common number) so that they both have a common denominator. Then just add the numerators and leave the denominator. Example:
5/6 + 3/4
The LCM of 6 and 4 is 12.
5/6 + 3/4 = (5*2)/(6*2) + (3*3)/(4*3) = 10/12 + 9/12 = 19/12

Adding decimals:
Line up the decimal points and add vertically. Bring the decimal point down.
``40.6
107.42
````9.0
+11.618
------------
168.638
So 40.6+107.42+9+11.618=168.638.

Hope this helps.

Answer 2

Wait, I just read how Adam said to do it. He gives a much easier/better explanation than me. Listen to him.

Here is how you add negative numbers...

for example...

-2 + -5 =-7

First the signs act like ones when multiplying, which is to say -1 * -1= 1 So think of it like this -1*2 + -1*5= -7 Since the negative ones make it positive you add the negative numbers together, but you keep their original sign... so just like 2+5=7, -2+-5=-7. If you add negative and positive numbers it is different. You end up subtracting and you take the sign of the larger number (so if you were adding -2 + 5= 3, -1*1= -1 so you subtract, to get 3, but you keep it positive since the 5 is the larger number and positive).

To add decimals and fractions together you just have to turn either the fraction into a decimal or the decimal into the fraction...

So you are adding 1/8 + 0.16 = 1/8 + 16/100 = now you want to simplify 16/100 and hopefully get it so it has a common denomanator with 1/8 so you would try 100/ x = 8 divind both sides by x, 100=8x, divind both sides by 8, 100/8 = x, 12.5=x

Now divide 16/12.5 =1.28 so you would have
1/8 + 1.28/8= 2.28/8 You want to simplify so divide both sides by 2 (the lowest comon denamonator) and you get 1.14/4. Divide 1.14 by 4 to get the decimial verson and you get 0.285. Hope that wasn't too confusing.

Answer 3

if you're adding a negative number and a positive number, all you do is subtract, if it's something like -2 + -2 do the same thing, the neg sign just means subtract. if you have a negative minus a negative, you add b/c the double neg cancels out. same goes for decimals and same thing with fractions, only remember, in order to add fractions they must have the same denominator. you can always check your answers with a calculator until you get the hang of it.

Answer 4

Well, if you've got a problem like:

1 + (-1)

Then just act like you're subtracting. It's the same thing.
Goes for fractions and decimals as well.

Feel free to email or IM for further questions

Answer 5

you need to transform the two to the two fraction or decimal, then you definately can upload them. 3/5 is 0.6, so which you have: 7.6 -4.8 = 2.8 any incorrect thank you to try this's 0.8 is 8/10 = 4/5, so which you have: 7 3/5 - 4 4/5 = 38/5 - 24/5 = 14/5 = 2 4/5, that's the comparable as 2.8, so which you get the comparable answer the two way.

Answer 6

By putting a plus sign (+) in between them.

Answer 7

the same way you add anything else