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Flashcards in Fractions Deck (11):
1

Fast fraction shortcut

Cross multiply and add (or subtract) the products. Then place the sum (or difference) over the product of the denominators

2

Key to multiplying fractions

Break them down

3

Dividing fractions

Flip the second fraction, BREAK DOWN NUMBERS, and then multiply

4

Complex numerator shortcut

Numerator of a complex fraction contains addition or subtraction, the fraction can be split as follows
(1+2)/6 --> 1/6 + 2/6 -->3/6 -->1/2

5

Reciprocal

Any two numbers whose products equals +1.
Some may not look like reciprocal such (1/sq.rt.3 * 3/sq.rt.3 = 3/3=1)
Some have more than one reciprocal (1/sq.rt.3 * sq.rt.3/1 = 1)

6

To compare fractions

Multiply from the bottom up (cross -multiply) and write the product over the corresponding numerator.

7

Positive integer X a proper fraction

...makes the value smaller

10 * (1/2) = 5

8

Dividing a positive value by a proper fraction...

...makes the value bigger

10 / (1/2) = 20

9

Squaring a proper fraction...

...makes the fraction smaller

(1/2)^2 = (1/4)

10

Taking the square root of a proper fraction...

...makes the fraction bigger

Square root of (1/2) = 0.71

11

FUQ - Fractions with unspecified quantities

Pick a number equal to the product of EVERY denominator in the problem