Multiplying Fractions 2
When multiplying mixed numbers we must first turn them into top-heavy fractions.
Once we have only fractions we just do the rule:
IT'S A CROSS SO CROSS THINGS OUT!
Here is another example:
Write out the question
Turn mixed into top-heavy
1 times 4 is 4 add 3 gives 7
2 times 7 is 14 add 4 gives 18
Find common factors (numbers to divide by)
7 and 7 are both divisible by 7 to leave 1 and 1
4 and 18 are both divisible by 2 to leave 2 and 9
Multiply across
Turn top-heavy back to mixed
2 into nine goes 4 with 1 left over
Once we have only fractions we just do the rule:
IT'S A CROSS SO CROSS THINGS OUT!
Here is another example:
Write out the questionTurn mixed into top-heavy
1 times 4 is 4 add 3 gives 7
2 times 7 is 14 add 4 gives 18
Find common factors (numbers to divide by)
7 and 7 are both divisible by 7 to leave 1 and 1
4 and 18 are both divisible by 2 to leave 2 and 9
Multiply across
Turn top-heavy back to mixed
2 into nine goes 4 with 1 left over
fractions index
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