Fraction help!!!

[KBKMNN]

I need help! Math is MY worst subject, but if I sit down, I can usually figure out an answer. However, I need help with 2 problems that are kicking my booty.

I can figure out how to add fractions with unlike denominators. So far it's been fairly easy, I just multiply the denominators to get my new one and then I cross multiply and then add whatever I get and I've always gotten the correct answer until now.

Maybe it's just my mind being stubborn, I don't know, but here is the problem and I do have the answer, but I can't figure out HOW it go to that.
5/12 + 7/8 = 17/24 But how? I come up with something totally different.

2/9 + 11/12 = 15/36 and again I'm not sure how.

Can someone explain in simple, simple terms how that's done?

[InHisGrip]

I need help! Math is MY worst subject, but if I sit down, I can usually figure out an answer. However, I need help with 2 problems that are kicking my booty.

I can figure out how to add fractions with unlike denominators. So far it's been fairly easy, I just multiply the denominators to get my new one and then I cross multiply and then add whatever I get and I've always gotten the correct answer until now.

Maybe it's just my mind being stubborn, I don't know, but here is the problem and I do have the answer, but I can't figure out HOW it go to that.
5/12 + 7/8 = 17/24 But how? I come up with something totally different.

2/9 + 11/12 = 15/36 and again I'm not sure how.

Can someone explain in simple, simple terms how that's done?


I don't come up with that answer either. Do you have an answer book and you're trying to match those answers? It wouldn't be the first time that the answer book was incorrect.

The first problem is 1-7/24 and the 2nd is 1-5/36

[MidnightCry]

I need help! Math is MY worst subject, but if I sit down, I can usually figure out an answer. However, I need help with 2 problems that are kicking my booty.

I can figure out how to add fractions with unlike denominators. So far it's been fairly easy, I just multiply the denominators to get my new one and then I cross multiply and then add whatever I get and I've always gotten the correct answer until now.

Maybe it's just my mind being stubborn, I don't know, but here is the problem and I do have the answer, but I can't figure out HOW it go to that.
5/12 + 7/8 = 17/24 But how? I come up with something totally different.

2/9 + 11/12 = 15/36 and again I'm not sure how.

Can someone explain in simple, simple terms how that's done?

Did you get the answer from the Teacher's Key? My daughter's in fractions right now, so I calculated the problem and got 1-7/24 as in "one and seven-twenty-fourths". Are you sure the answer wasn't missing a hyphen?

Same thing with the second problem -- should be 1-5/36 as in "one and five thirty-sixths".

[BlessedinHim]

5/12 + 7/8 = 17/24
5/12 + 7/8 = ____
10/24 + 21/24 = 31/24
31/24 = 1 7/24

2/9 + 11/12 = 15/36
2/9 + 11/12 = ______
8/36 + 33/36 = 41/36
41/36 = 1 5/36

[vmoon]

I need help! Math is MY worst subject, but if I sit down, I can usually figure out an answer. However, I need help with 2 problems that are kicking my booty.

I can figure out how to add fractions with unlike denominators. So far it's been fairly easy, I just multiply the denominators to get my new one and then I cross multiply and then add whatever I get and I've always gotten the correct answer until now.

Maybe it's just my mind being stubborn, I don't know, but here is the problem and I do have the answer, but I can't figure out HOW it go to that.
5/12 + 7/8 = 17/24 But how? I come up with something totally different.

2/9 + 11/12 = 15/36 and again I'm not sure how.

Can someone explain in simple, simple terms how that's done?


Yes, hold on. you've got 5/12 +7/8
you need a common denomonator and it is 24 because.... look at both bottom numbers they are 12 and 8 right? You need to find the smallest number that both 12 and 8 can be divided into. Ok? That number is 24.

Now we have a common denomonater of 24.

Now... 5/12 =?/24.... how many12's go into 24? answer 2

ok, now say 2 times 5 =10 .... (look at the 5 on top of the 12)
now we have 5/12=10/24


do the same thing for 7/8
7/8=?/24...how many 8's go into 24? answer 3
now say 3times7=21 (look at the 7 on top of the 8)
7/8=21/24 ok here are your new fractions

10/24+21/24.... add 10+21=31 right? new fraction is 31/24 but..... that's an improper fraction because the bottom number is smaller than the top number so.... divide the 24 into the 31 and you get 1and7/24

I do hope I didn't make it more confusing.

[fracturedInfinity]

5/12 + 7/8 = 17/24 But how? I come up with something totally different.

2/9 + 11/12 = 15/36 and again I'm not sure how.

Can someone explain in simple, simple terms how that's done?

Where did you get those answers from? They are wrong. I tried the other signs too to see if maybe they weren't addition, but none of them worked out.

:scratch


Ohh...

Looks like you got your whole numbers stuck on to the single digit that should be in the numerator.

17/24 should be 1 and 7/24
15/36 should be 1 and 5/36

[KBKMNN]

I PM'd InHisGrip and told her what a dufus I had been. :heh :doh
Those were the correct answers that she came up with, that I had read the answers wrong. I think maybe I am needing glasses.

[Itiswell]

:)That's exactly when I figured out I needed reading glasses - the small print in the answer keys was getting to me! I would check my son's work, he would rework the problem and come up with the same answer, then I'd realize my mistake.:oops

Fortunately, he is a good sport, but was glad when I finally broke down and bought reading glasses.

[KBKMNN]

I need help again.
2 1/3 - 1 7/9 = 5/9
Can someone show me how they solved that? I thought that subtracting was basically like adding where you multiply the denominators to get your common denominator and then cross multiply and then subtract. I get something different when I do it that way. Is there another way I should be doing it?

Also 2 2/7 - 1 8/9 = 25/63
Again, I came up with something different. I came up with 36/63
Can someone tell me what I'm doing wrong? I feel so dense here!

[InHisGrip]

Okay....here ya go.

In the first problem you need to make both fractions into improper fractions. The way you do that is 2 X 3 +1, so your new fraction would be 7/3. 1-7/9 is 1 X 9 + 7, so it would be 16/9. Your problem now looks like this 7/3 - 16/9. Now find your common denominator, which is 9. Change 7/3 to 21/9 by multiplying both top and bottom by 3. You now have 21/9-16/9. The dfference between 21 and 16 is 5. Your answer is 5/9. Make sure this one makes sense before we do the next one.