math question - can anyone help?

[chickie1]

greetings fellow flashers, it is I, still around and happily on unemployment. soaking up the wonders of no bosses no timelines, no start/finish times. its GREAT!!!
I do have a question to ask, it is fairly simple, it has been some 20 years since my high school and I have to brush up on my math skills, does anyone know fractions?
I understand them mostly, but when it comes to the common denominators some of it twists my mind strings. I know how to get the common, but unsure on how the handle the rest. dont know if the top part of the fraction needs to be either added,divided or multiplied by the common or not.
example 2/3 x 5/8 the common is 24, do I have to do anything with the above number other than multiply across?

also, if anyone could just check to see if the following are correct it would be great

5/8 + 2/16 = 7/16 ?

6/7 - 4/5 = 2/35 ?

I may need help

[iCEBERG2000]

Originally posted by chickie1

5/8 + 2/16 = 7/16 ?

6/7 - 4/5 = 2/35 ?

I may need help

5/8 + 2/16 = 12/16 = 3/4

6/7 - 4/5 = 30/35 - 28/35 = 2/35

[Napalm]

Originally posted by chickie1
5/8 + 2/16 = 7/16 ?

I may need help [/B]

The first one is wrong, the second right

5/8 + 2/16 = 12/16 = 3/4

If you multiply the bottom, you must also multiply the top by the same number.

[chickie1]

ok so can someone explain this to me. if you find a common denominator wether it be addition subtraction & so on. you still need to muliply the top number even if its an addition problem

[chickie1]

Originally posted by iCEBERG2000

Originally posted by chickie1

5/8 + 2/16 = 7/16 ?

6/7 - 4/5 = 2/35 ?

I may need help

5/8 + 2/16 = 12/16 = 3/4

6/7 - 4/5 = 30/35 - 28/35 = 2/35

Can you please explain this to me, how did you get 12 and 30. this is what I am missing the boat on

[Napalm]

Originally posted by chickie1
ok so can someone explain this to me. if you find a common denominator wether it be addition subtraction & so on. you still need to muliply the top number even if its an addition problem

Yes, thats correct.

[iCEBERG2000]

Originally posted by chickie1
ok so can someone explain this to me. if you find a common denominator wether it be addition subtraction & so on. you still need to muliply the top number even if its an addition problem

for sure!

3/4 + 7/8 = (3*2/4*2) + 7/8 = 6/8 + 7/8 = 13/8


[Edited by iCEBERG2000 on 11-26-2001 at 09:09 AM]

[chickie1]

thanks guys, now I am really confused. thought I could count on someone here. if you have
5/8 + 2/16 = 12/16? i thought 5x2 was 10 not 12

[iCEBERG2000]

Originally posted by chickie1
thanks guys, now I am really confused. thought I could count on someone here. if you have
5/8 + 2/16 = 12/16? i thought 5x2 was 10 not 12

yeah 5*2 = 10 but you add 2/16 to 10/16 so that is 12/16 right?

[chickie1]

I was missing the part of if you have to change the common you have to mulitply the top number of the fraction by the amount of times it is divisible by, that was all I needed to here.