SOLUTION: i need refreshment on +, -, mulipling, and dividing fractions. My little sister keeps coming to me for help and i graduated 5 years ago and for got it all.

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Question 270886: i need refreshment on +, -, mulipling, and dividing fractions. My little sister keeps coming to me for help and i graduated 5 years ago and for got it all.
Found 2 solutions by rfer, JBarnum:
Answer by rfer(16322) About Me  (Show Source):
You can put this solution on YOUR website!
minus times a minus equals a plus
plus times a plus equales a plus
minus times a plus equals a minues
the three are also true for division
remember division of fractions, invert the second fraction and multiply.
Does that help?

Answer by JBarnum(2146) About Me  (Show Source):
You can put this solution on YOUR website!
with adding and subtracting you will need a common denominator for example:
3%2F5%2B3%2F10=9%2F10 multiply the 3/5 by 2/2 and u get 6/10 so 6+3=9
3%2F5-3%2F10=3%2F10 multiply the 3/5 by 2/2 and u get 6/10 so 6-3=3
With multiplying fractions u multiply straight across examples:
%285%2F6%29%284%2F7%29=20%2F42 u can simplify to 10/21
or
%285%2F3cross%286%29%29%282cross%284%29%2F7%29=10%2F21 do cross cancelations to make simplifying easier
with dividing fractions is where it gets tricky. when i divide a fraction by a fraction i alwas multiply by the reciprical of the second fraction.example:
%282%2F9%29%2F7=%282%2F9%29%287%2F1%29=14%2F9
the tricky part is when u see something like this:
%28%282x%2B3%2F2%29%2F%284%2F5%29%29
then u just need to take it slow
%28%282x%2B3%2F2%29%285%2F4%29%29
%2810%2F4%29x%5E2%2B%2815%2F8%29 If x=2 then u could solve this
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%2810%2F4%29%282%29%5E2%2B%2815%2F8%29
95%2F8 is what you should get if u try working out this example