fractions need all stept please?

Question

1. 1/4 + 2/5
2. 1 3/4 + 2 1/12
3. 3/4 - 1/6

Answer 1

Well you need to find the greatest common factor (GCF) for all of these:

1. So the GCF for this problem is 20 b/c 20 is divisible by 4 and 5. So you multiply each fraction's top and bottom to get the denominator to equal 20.
1/4 x 5/5 = 5/20
2/5 x 4/4 = 8/20
So 5/20 + 8/20 = 13/20

2. Mixed fractions: What you need to do first is, For 1 3/4 You multiply 1 x 4 (the denominator) and then add the numerator, 3. And keep the denominator the same. So therefore, you 1 3/4 turns into 7/4. Do the same for 2 1/12. Multiply 2 x 12, and then add 1. This equals 25/12.
So you have 7/4 + 25/12. Next you must find the GCF to add these. It is 12. So all you need to do is multiply 7/4 by 3/3 to get a denominator of 12.
7/4 x 3/3 = 21/12
So 21/12 + 25/12 = 46/12
You need to reduce 46/12 divided by 2/2 = 23/6 or 3 5/6

3. The GCF is 12.
3/4 x 3/3 = 9/12
1/6 x 2/2 = 2/12
Therefore, 9/12 - 2/12 = 7/12

Answer 2

In order to add and substract fractions, all denominators in the problem need to be the same so you have to do some conversions.

Find the least common multiple of the denominators in each problem then convert your fraction using this as the denominator in both fractions: for example if you want to add
1/2 + 2/3 =

you look at the two denominators. 2x3 = 6 so 6 is the least common multiple.

Change 1/2 to a fraction with a denominator of 6.
You do this by dividing the denominator of your original fraction into 6 and then multiply your answer by the numerator of your fraction. This will give you the new nominator. You do the same thing with subtraction problems.

I'll do Number 1. and then you can do the rest.

1/4 + 2/5 =

The least common multiple is 20 (4x5)

the first fraction is 20/4 x 1 = 5 (new nominator)

5/20 +

the second fraction is

20/5 x 2 = 8 (new nominator

your new fraction is 8/20

Now your problem is: 5/20 + 8/20 = 13/20

Your answer is 13/20. This fraction cannot be reduced (there is no number that will divide evenly into both numerator or denominator.) If you get an answer that you can reduce, then you should reduce it.

Hope this helps.

Answer 3

Easy - as 1, 2, 3: Now relax and take a deep breath, breathe -

Change to decimals:

1. 1/4 = 1 divided by 4, = .25 1.00/4.0=.25
2/5 = 2 divided by 5, = .40 2.0/5.0= .40
add these together

2. 1 and 3 divided by 4 = 1.75
2 and 1 divided by 12= 2.083
add these together

3. 3 divided by 4 = .75
1 divided by 6 = .16
subtract these (.75 - .16)

See how easy this is when you convert the fractions to decimals by dividing.

Now the more difficult way is to find the lowest common denominator.

4 x 2 = 8, but that does not work because 5 does not go into 8 evenly,
4 x 3 = 12 but that does not work because 5 does not go into 12 evenly,
4 x 4 -= 16 but that does not work because 5 does not go into 16 evenly,
4 x 5 = 20 --- and that works because 5 goes into 20 evenly,
x 5 = 20 for a common denominator

1. 4 goes into 20, 5 times so to convert it= 5 so it's 5/20, or 1/4
5 goes into 20, 4 times, so to convert it= 4 x the 2 which is the number on top or the numerator, 8/20, or 2/5

2. 4 and 12 = have a common denominator, now go back to the number on top, and that is 3,
3 x the number that 4 goes into the 12 common denominator, now multiply the 3 x 3 or -- 9 /12, = 3/4,
so you add 1 9/12 plus
---- 1/12 (1 9/12 + 1/12 = and you provide the answer)

4x 2 = 8 but that does not work for 6, so try again
4 x 3 = 12, and that works because 6 goes into 12 2 x so,
the common denominator for this problem is 12.

Now you do the subtraction after you find the common denominator (which I gave you is 12,
and you divide the 4 into the common denominator,
and then multiply the top number or the numerator (which is 3 in this case by the number of times the 4 goes into the common denominator,
now do the same for the 1/6,
one is the numerator
6 is the number before converting it to the common denominator.

I do hope this helps you understand

GOD bless us one and all, always
MBA-Boston University
CPA-retired

Answer 4

The key to the problems in your question is finding the least common multiple LCM of the denominator in your fractions. The LCM of two numbers is obtained by finding the lowest number that can be divided by the two numbers given. For example, the LCM of 2 and 5 is 10, because 10 is the lowest number divisible by both 2 and 5.

1. The first step to this question is obtaining the LCM. In this case, the LCM is 20, because that is the smallest number that is divisible by both 4 and 5. For the first fraction, you must multiply both the numerator and the denominator by 5 (5 is the quotient of 20/4). Thus, you get 5/20 as the product. For the second fraction, you must multiply both the numerator and the denominator by 4 (from this product, you obtain the fraction 8/20).

Now that you have two fractions with common denominators, 5/20 and 8/20, you can simply add the numerators. Thus you come up with 13/20 as the answer.

2. LCM of the two denominators, 4 and 12, is 12. Thus 1 9/12 + 2 1/12. Answer to this problem is 3 11/12.

3. LCM of these two denominators is 12. Thus 9/12 - 2/12. Answer to this problem is 7/12

Answer 5

When adding or subtracting fractions, you need to find a common denominator first. To do this find a number that both denominators can divide into evenly.

1. for 4 and 5, the common denominator is 20.
Find equivalent fractions. 1/4 = 5/20 and 2/5 = 8/20

Now add them together 1/4 + 2/ 5 = 5/20 + 8/20 = 13/20
Only add the numerators...leave the denominators alone!

2. Common denominator here is 12
3. CD is 12 here as well.

Just follow the same steps...good luck!

Answer 6

I will tell you the steps but do the actual math for yourself.

For #1 and #3 you need to get common denominators first (20 and 12, respectively) then you will be able to just add/subtract the top numbers.

For #2 you need to get rid of the whole number by multiplying the whole number and the denominator together, then add the numerator to that number. The answer you get for that becomes your new numerator and put it over the same denominator you had before. In order to add the two numbers you get common denominators (it looks like 12 in that case, also) and then just add the numerators.

If you can you should reduce your answers at the end.

Answer 7

1/4 + 2/5, 1/4x5/5 + 2/5 x 4/4, 5/20 + 8/20 = 13/20

1 3/4 + 2 1/2, 4/4 +3/4= 7/4 + 4/2 + 1/2= 5/2, 7/4 + 5/2 x 2/2=10/4, 7/4+10/4 = 17/4, 17/4=4 1/4

3/4-1/6, 3/4x3/3=9/12 - 1/6x2/2=2/12 9/12-2/12= 7/12

Answer 8

1. you need to change them to like fractions, find the LCD or lowest common denominator, and multiply
1/4 x 5/5 = 5/20 (5/5 is okay to multiply by seeing as it is equal to one, so is 4/4)
2/5 x 4/4 = 8/20 then add them together and simplify
5/20 + 8/20 = 13/20

You do the same thing for the other ones