Math homework help 
multiplying fractions
and mixed numbers
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Multiplying fractions and mixed numbers 1
Multiplying fractions and mixed numbers 2
Multiplying fractions and mixed numbers 3
Multiplying fractions and mixed numbers 1
What I received

What I sent back

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Multiplying fractions and mixed numbers 2
What I received

What I sent back

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Multiplying fractions and mixed numbers 3
What I received

What I sent back

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More sample maths homework help
Tip: When multiplying fractions and mixed numbers, be sure to cross cancel common factors between numerators and denominators before multiplying them out. You don't want to multiply numbers to get two larger numbers (numerator and denominator) and then divide those numbers to bring them down (that is, simplify the answer).
Take for example
^{7}⁄
_{9} ×
^{45}⁄
_{28}
If you follow the rule of fraction multiplication, you get
^{(7 × 45)}⁄
_{(9 × 28)} (two multiplications, takes time)
=
^{315}⁄
_{252}
Then you need to reduce
^{315}⁄
_{252} to it's lowest term, which means you need to find a number that can divide both 315 and 252 and keep dividing until you get the answer in the simplest form. The final answer is
^{5}⁄
_{4} = 1
^{1}⁄
_{4}.
If you do it in this method, you don't do anything wrong but that's not the best way to do the multiplication. Multiplying and then dividing is as good as taking one step to the left and one step to the right which effectively means you come back to the same place. No doubt that takes time and therefore, is an inefficient way to multiply fractions.
Instead, use cross reduction first. Divide 7 from the numerator and 28 from the denominator by 7. That leaves 1 in place of 7 and 4 in place of 28.
Similarly, divide 45 from the numerator and 9 from the denominator with 9. That leaves 5 in place of 45 and 1 in place of 9.
^{7}⁄
_{9} ×
^{45}⁄
_{28}
=
^{71}⁄
_{91} ×
^{455}⁄
_{284}
=
^{5}⁄
_{4} = 1
^{1}⁄
_{4}.
Don't you find this easier?