Fraction arithmetic

To multiply two fractions, you

• multiply across both top and bottom

• multiply across the top but leave the bottom alone

• flip the second fraction and then multiply across top and bottom

To divide one fraction by another, you

• multiply across both top and bottom

• multiply across the top, but leave the bottom alone

• flip the second fraction, and then multiply across both top and bottom

Before you can subtract one fraction from another,

• you must change the second fraction into its reciprocal and then add the numerators

• the denominators must be the same

• both fractions must be positive

(3/7)(4/5) =

• 7/12

• 12/35

• 15/28

• 1

1/2 - 1/5 =

• 0/10

• 1/10

• 3/10

• 5/2

11/7 - 2/7 =

• 9/0

• 9/7

• 4/5

• 22/49

What is the multiplicative identity?

• 0

• 1

• the opposite

• the reciprocal

What is the one rational number that has no reciprocal?

• -1

• 0

• 1

• π

4/7 divided by 1/3 =

• 12/7

• 7/12

• 3/4

• 4/21

Simplify (36 + 6)/66 to its most reduced form.

• 21/33

• 14/22

• 37/11

• 7/11