Question

Elijah is braiding a cord that will be 28/24 of a yard long. he has finished 19/24 of a yard. How much more does he need to braid?

Answer 1

Simple subtraction of fractions problem:

\[\frac{28}{24} - \frac{19}{24} = \frac{28 - 19}{24} = \]

Answer 2

ok, therefore the answer would be 4/24 right?

Answer 3

Does 28 - 19 = 4?

Answer 4

I mean 9/24

Answer 5

Yes. Can you simplify that further?

Answer 6

Depending on the circumstances, 9/24 might be the most convenient answer, but it's good to keep up the skill at reducing fractions, too :-)

Answer 7

however they only have
1/24 or 23/24 or 1/6 or 1/12 to choose from.....

Answer 8

Are you sure you copied the problem correctly? Are there units on the answers?

Answer 9

These are the multipale chocie to choose from.

23/24yard
1/6 yard
1/12 yard
1/24 yard

Answer 10

I came up with 9/24, but this is not one of my choices

Answer 11

Okay, they are asking for an absolute amount, not a fraction of what's been done or anything like. None of those equal 3/8 of a yard, and that's exactly what 28/24 - 19/24 equals. Could that 8 actually be a 0 with some crap in the middle? That would give an answer of 1/24, which is among the choices.

Answer 12

lol, no I copied the question from the source. that's what threw me. they want to know how much more does elijah need to braid. help, help

Answer 13

Well, if the problem is correctly stated, the answer is 3/8 or 9/24 of a yard. If the answer has to be one of those choices, the problem is incorrectly stated. If you can't ask the person who wrote the problem, I would go with 1/24 in the hopes that it was a single-character typo in the problem.

Answer 14

I am sorry it's 23/28

Answer 15

I mean 23/24

Answer 16

sorry, this is driving me crazy

Answer 17

therefore, 4/24 needs further working right?

Answer 18

Is 23/24 the size of the braiding cord Elijah wants to make ?

Answer 19

4/24 = 1/6

Answer 20

Elijah is braiding a cord that will be 23/24 of a yard long. he has finished 19/24 of a yard. How much more does he need to braid?

Answer 21

how did you come up w/1/6

Answer 22

23/24 - 19/24 = 4/24 = 1/6
I just reduced 4/24 to get 1/6

Answer 23

ok, how did you reduce, I am trying to teach my granddaughter how to reduce it........

Answer 24

what number goes into 4 and 24 evenly ? 4 does. 4 goes into 4 one time and 4 goes into 24, six times.

Answer 25

You are so special for taking out this time with me, thank you.

Answer 26

do you understand how to reduce ? because if you don't, I can give you more examples

Answer 27

one more example wouldn't hurt, thanks - teach me,

Answer 28

3/18
what goes into 3 and 18 evenly ?

Answer 29

3 goes into 3 one time, and 3 goes into 18 six times. so would the answer be 3/6

Answer 30

no......it would be 1/6 not 3/6

Answer 31

oh, thats right because 4 goes into 4 one time. Ok, give me one more.

Answer 32

6/18

Answer 33

1/3

Answer 34

Ah, good eyes, spotting that it is supposed to be 23/24!

Answer 35

is 1/3 correct?

Answer 36

correct. It is easier to use the largest number that will go into both numbers, but even if it isn't the largest number, it will still work. For instance if you used 6...6/18 = 1/3 and if you used 3....6/18 = 2/6 = 1/3.
By not using the largest number, this just means you might have to reduce more then once. Now if you get an answer like 5/7. What goes into 5 and 7 evenly ? Nothing does, so this fraction will not reduce. Understand ?

Answer 37

To reduce a fraction, in general, rewrite it as all of its prime factors. Prime numbers are those such as 2, 3, 5, 7, 11, 13, etc. which don't have any divisors except 1 and themselves. 2 is the only even prime number. So, to reduce \(\dfrac{4}{24}\) we could write
\[\frac{4}{24} = \frac{2*2}{2*2*2*3}\] and then cancel matching items from the top and bottom giving us \[\frac{1}{2*3} = \frac{1}{6}\]

Answer 38

lets try this one 5/6 - 1/6 so this would be 4/6 = 1/6 right? or not?

Answer 39

or 2/3

Answer 40

\[\frac{5}{6}-\frac{1}{6} = \frac{4}{6} = \frac{2*2}{2*3} = \frac{2}{3}\]

Answer 41

2/3 is correct....2 goes into 4 two times and 2 goes into 6 three times

Answer 42

now how about if its like this?
1/12 + 3/4 =

Answer 43

turn mixed numbers into improper fractions, then add. Do you know how to do that ?

Answer 44

oops read it wrong

Answer 45

no, because I would have just said 4/16

Answer 46

1/12 + 3/4
To add fractions you have to have the same denominator. If the denominators are not the same, you have to make them the same. What is the lowest number that 4 and 12 will go into ? 12 is the lowest number. So, you have to make the denominator 12. So, in this case 1/12 stays the same but 3/4 will change.
Look at 3/4 and you want 12 to be the denominator.....4 goes into 12 how many times ? 3 times. Now take that 3 and multiply it by the numerator (3) and put that answer over 12. So, now you have 9/12.
Your problem now is 1/12 + 9/12 = 10/12 = 5/6

Answer 47

wow, stick a fork in me becasue I am done. I have copied all your notes to study, so that I can break it down to him, again thank you so much, I need a cup of coffee after that. lol you are very special. again thanks

Answer 48

that is what we are here for....if you have any more problems, we are here to help :)

Answer 49

Remember this as well.....you have to have a common denominator in both adding and subtracting fractions, but not when multiplying or dividing fractions.

Answer 50

You need to find a common denominator. Ideally, that common denominator will the Least Common Multiple (LCM) of all of the denominators in the problem. To find the LCM, you take the prime factors of each denominator:

\[4 = 2*2 = 2^2\]\[12 = 2*2*3 = 2^2*3\]
Then you multiply the highest power of each different factor:
\[2^2*3 = 12\]
This seems like more work than just spotting that 12 = 3*4, but when you have a big ugly number, it saves work.

For example, \[\frac{1}{8}+\frac{1}{9}+\frac{1}{10}+\frac{1}{11}\]
\[8 = 2^3\]\[9= 3^2\]\[10=2*5\]\[11=1*11\]
Now we combine the highest power of each factor:
\[2^3*3^2*5*11 = 8*9*5*11 = 3960\]So our answer will be \[\frac{x}{3960}\] (for the appropriate value of \(x\).

Answer 51

As an exercise, try working out that fraction. You'll multiply the 1/8 by 9*10*11/9*10*11, the 1/9 by 8*10*11/8*10*11, and so on, then add the results.

Answer 52

good explaining whpalmer4 :)

Answer 53

That looks like such an innocuous little fraction, doesn't it? :-)

Answer 54

lol....it sure does

Answer 55

Darn....I should have explained to her what a fraction like 4/4 equals. Do you think she will know that ?

Answer 56

One more thing:

If you are doing an algebra problem, not just adding a few fractions, you can make life much easier by not doing fractions at all!

For example, say our fiendish fraction problem was
\[\frac{x}{8}+\frac{1}{9}+\frac{1}{10}+\frac{1}{11} = 1\]We could find the common denominator and convert everything over to it, but that's a bunch of work. Instead, we just multiply both sides of the equation by all of the denominators:
\[(8*9*10*11)(\frac{x}{8}+\frac{1}{9}+\frac{1}{10}+\frac{1}{11} )= 1(8*9*10*11)\]which simplifies to \[(9*10*11)x + 8*10*11 + 8*9*11 + 8*9*10 = 8*9*10*11\]\[990x + 2392 = 7920\]and it's just a short hop and a skip to \[x = \frac{2764}{495}\]

Answer 57

This works because the product of all of the denominators is clearly a multiple of all of them. If the numbers are all relatively prime (they share no factors other than 1), this will in fact be the least common multiple (or least common denominator).