Back to school fractions, any body wanna help?

Question

Just to refresh my mind, explain what fraction is.

Give me a few examples and step by steps.

I want addition, multiplication, subtraction, and division.

Fractions.

Thanks a lot!!

Answer 1

well to add or subtract fractions, all the fractions need to have the same denominator (number on the bottom).  then you just add or subtract the numerators (numbers on the top) the denominator stays the same:

1/5 + 2/5 = 3/5

6/9 - 3/9 = 3/9

but if you need to add or subtract two fractions w/different denominators, you have to change them to make the denominators the same.  if you had this for example:

3/5 + 2/25 = ?

you can make the 3/5 have a denominator of 25 by multiplying the fraction by 5/5 (whatever you do to the bottom, you do to the top.  So now 3/5 turns into 15/25.  now the problem looks like this, and you just add it:

15/25 + 2/25 = 17/25

multiplying fractions is easy...if you had this for example:

2/8 x 3/5 = ?

you just need to multiply across: multiply the numerators of both fractions (2 x 3) and the denominators of both fractions (8 x 5):

2/8 x 3/5 = 6/40

Dividing isn't hard either.  If you had this for example:

6/10 / 3/4

you need to take the second fraction (3/4) and switch the top and the bottom (make it 4/3) this is called the reciprocal.  then you multiply the two fractions (no dividing):

6/10 x 4/3 = 24/30