How do change decimals into fractions?

Answer 1

Depends on the #. Here is a tip though...
Lets say the # is 3.14
We know that 3 is the whole #. the .14 is going to be over 100 so,

3.14= 3 and 14/100.
Now you reduce.
14 and 100 are both divisible by 2, so the fraction is now 7/50. That ia called an equivalent fraction.

Baiscally, here is how to set it up:

.1 = 1/10 because the one is in the tenths place
.33 = 33/100 beacuse the last digit is in the onehundreths place.

If ya need more help, let me know!

Answer 2

First, lets give the number in question a name, say x. Since x is rational, its decimal expression will start to repeat in blocks after some point.

Look at the decimal expansion and find out what the repeating block is and the number of digits in each block. Multiply x by a power of 10 to shift the number over one block then subtract. You will have an integer times x equals a terminating decimal (or even possibly an integer). If there is still a decimal, you can multiply by some power of 10 to get all integers. Then you can do a division to get x equals a fraction.

The main idea is that we do some manipulation so that through subtraction the repeating blocks are subtracted off. Then we can continue with the division.

An example:

Say x=2.761919191919....

The repeating block is the block 19 over and over. It has 2 digits, so we'll be multiplying x by 10^2 = 100 in this case. Then we'll subtract.

100x = 276.1919191919...
x=2.761919191919...
------------------------------------
99x = 273.43

(If the decimals lined up in this display, you'd see that the blocks are situated right above each other.)

So we have an equation in which the coefficients are terminating decimals. Since we have 43 hundredths on the right, if we multiply both sides by 100, we'll get all integer coefficients:

9900x = 27343.

We divide to get

x=27343/9900.

Some of the other answerers talked about multiplying the decimal by some power of 10 then dividing to get the fraction. While this works for terminating decimals, it doesn't work generally.

Cheeeeee......eeeers!

Answer 3

You put the numbers in the decimal as a fraction over the place of the decimal (so it isn't always over 100)
For example:
0.5 = 5/10
0.05 = 5/100
0.055 = 55/1000

Answer 4

count the number of digits next to the decimal and multiply that number with 10 put that number in the denominator of that number by removing the decimal

Answer 5

Multiply by 1 in the form 10/10 until you have cleared the decimal point. Then reduce to lowest terms:
eg.
0.356*10/10 = 3.56/10
(3.56/10)*(10/10) = (35.6/100)
(35.6/100)*(10/10) = 356/1,000
356/1,000 = 178/500 = 89/250

Answer 6

put the decimal over 100 and reduce to lowest terms.

.75 = 75/100 = 3/4

Answer 7

lets say you have a number 0,245 and you want to change it into a fration:
0,245=245/1000 and now you can reduce
245/1000=49/200
lets say you have a number 3,145
then again
3+145/1000 = 3+29/200 = (3*200+29)/200= 629/29