SOLUTION: how do u multiply add subtract and divide fractions?

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Question 7551: how do u multiply add subtract and divide fractions?
Answer by bonster(299) About Me  (Show Source):
You can put this solution on YOUR website!
WHEN ADDING FRACTIONS,
1) look for a common denominator.
ie: 3/7 + 2/5
The common denominator for this would be 35
%283%29%285%29%2F35+%282%29%287%29%2F35

2) add the numerators and put it over the denominator, 35.
%2815%29%2F35+%2814%29%2F35=29%2F35



WHEN SUBTRACTING FRACTIONS, the procedure is the same to adding fractions, except that you're subtracting. Let's use: 3%2F7 - 2%2F5
1)Look for a common denominator
%283%29%285%29%2F35-%282%29%287%29%2F35
2) subtract the numerators and put it over the denominator
%2815%29%2F35-%2814%29%2F35=1%2F35



WHEN MULTIPLYING FRACTIONS, MULTIPLY ACROSS
=(3%2F7)(2%2F5)
=14%2F35
Reduce when necessary:
=14%2F35=2%2F5


WHEN DIVIDING FRACTIONS, multiply the numerator and denominator by the reciprocal of 2%2F5 which is 5%2F2
=(3%2F7)/(2%2F5)
(3%2F7)*(5%2F2)/(2%2F5)(5%2F2)

Then the denominators cancel out and you're left with:
(3%2F7)*(5%2F2)
solve this as you would when multiplying fractions...
=15%2F14
Simplify when necessary
1 1%2F14