for all you math geniuses...

[mommanessy247]

i need some math help here. i'm trying to do some fraction addition and some of it i figured out but this is what i'm struggling with...
first off lemme tell you WHAT i'm doing...
i'm trying to calculate how many ounces of formula my newborn daughter had over the course of yesterday to see if she'd gotten the total 20 oz the doc wants her to get every day. (she's been having eating issues resulting in dramatic weight loss and dehydration landing her in a childrens hospital for 2 days...not fun.) and we are on strict doctor's orders that our daughter is to receive no less then 20 oz p/day if we can help it. so here's the total oz. p/feeding she took throughout the day & night yesterday...and then i'll tell you where i'm having the problem...
1 1/2
2
1
1 2/3
1
1 1/2
1/2
2
2

so far i was able to add the whole #'s and i got 11, then i added 2 of the 1/2's for another whole bringing that whole # up to 12. that left a 1/2 and the 2/3...so the math problem for me now is
12 1/2 + 2/3.
that 2/3 is my problem. i tried calculating it online and i got alot of something about uncommon denominators and changing them and i'm like
"huh?! "
the only thing i can do with fractions is adding the whole #'s and adding the simple fractions like the 1/2's to make whole #'s but that rogue 2/3 is throwin' me off and the computer couldnt even help me out.
now, from looking at those #'s it's blatantly obvious that my daughter did not get the 20 oz. the doctor wants her to get. we've got alot of issues with her taking just enough to satisfy her stomach and then clamping up tighter then a clam and at that point it's impossible to get more in her without forcing it, which we're really not comfortable doing.
this is my 1st time with a difficult eater, my other 2 kids were pirahnas at birth pounding down 2-3 oz right off with my oldest daughter taking 4 oz by 1-2 months of age.
so anyways, if you can help me figure out that 12 1/2 + 2/3 that'd be great. it looks to me like the total is gonna be somewhere in the 13-13 1/2 range.

[Twisted Reptiles]

13 1/6 oz (or 13.17 if you prefer decimals)

[Skittles1101]

13 1/6

ahhh you got it first

The common denominator of 1/2 and 2/3 is /6
/2 = /6
/3 = /6
2 goes into 6 3 times, so 1/2 = 3/6
3 goes into 6 2 times, so 2/3 = 4/6
3/6 + 4/6 = 7/6 aka 1 1/6

Hope that wasn't too confusing!

[mommanessy247]

haha thx Lgray it's official...
i'm now cuz of all that...
but i think i understood the gist of your explanation though.
to be honest i never really got too deep into fractions even through high school. i didnt even get into long division. i had to have some special ed classes cuz i've got issues and math was (& still is) my # 1 nemesis! i'm GREAT with reading & spelling though. it's funny cuz in my current relationship whenever there's math involved my bf is all over it...he's my human calculator in the grocery store. he can keep an estimated running total of our items and at the end of the trip through the store when we ring up our goods his final count is rarely more then a couple dollars off then the actual total. he's got some skills, lol.
whenever he cant spell something he asks me.
so we're somewhat of a team and we always say that we're each other's other 1/2, take away one of us, the other is incomplete and kinda lost.

[Pyth]

Hey there,

A few folks have given you the correct result, which is 13.6 approximately. However for further reference, you may want to know how to do it your self, so below is an easy sheet.

Fractions

1/2 = .5
2/3 = .66

[TheRatMan]

yea if you have problems with fractions all you have to do is simplify them into decimals like this...
1/2 = .5 Divide the top number in the fraction in this case 1 by the bottom number ie. 2

in case you were wandering how Pyth came up with those numbers

[Pyth]

Beg pardon

A few folks have given you the correct result, which is 13.16 approximately (ignore earlier post).

However for further reference, you may want to know how to do it your self, so below is an easy sheet.

Information most pertinent to your equation,

Fractions

1/2 = .5
2/3 = .666666666666


I tried to make a reasonable columned table, but the forum doesn't support the formatting I used;

Method

1 1/2 = 1+.5 = 1.5
2 = 2 = 2
1 = 1 = 1
1 2/3 = 1+.66 = 1.66
1 = 1 = 1
1 1/2 = 1+.5 = 1.5
1/2 = .5 = .5
2 = 2 = 2
2 = 2 = 2

Sum of each column (since they're the same numerically) is 13.16. So you can use the calculator at whichever step is easiest for you to compute the answer. (Or do it by hand )

[BPelizabeth]

Change the demonimators to all the same number then you can add them up easy

hence

2/3 and 1/2

change the denominator to (bottom number to the same number) lets go with 6

2/3 x2=4/6
1/2 x3=3/6
add em up.....7/6 which is 1 whole and 1/6