(3)
What is the denominator in 7/8?
_____________
The denominator in 7/8 is 8.
(4)
What is the denominator in 12/5?
_____________
The denominator in 12/5 is 5.
1-3. COMMON DENOMINATORS
a. When fractions have the same number in the denominator, they are said to
have COMMON DENOMINATORS. For example: 1/8, 2/8, 5/8, 7/8, and 3/8 all have a
COMMON DENOMINATOR of 8.
b. Sometimes there is a need in mathematics to find a common denominator.
For example, before fractions may be added or subtracted, the denominators of all the
fractions in the problem must be the same.
c.
The following rules must be applied when working with fractions:
(1)
If the numerator and the denominator of a fraction are multiplied by the
same number, the value will not change.
For example: Multiply the numerator and denominator of 1/2 by 2.
2x2= 4
1x2 = 2
2x2
4 then: 4 x 2 8 , and so forth.
In this example: 1/2, 2/4, and 4/8 all have the same value.
(2)
If the numerator and the denominator of a fraction are divided by the
same number, the value of the fraction will not change.
For example:
22 =1
42=2
8 2 4 then: 4 2 2 , and so forth.
Again: 4/8, 2/4, and 1/2 all have the same value.
d.
To find a COMMON DENOMINATOR for the fractions 1/4, 3/8, and 5/16:
(1)
Find the largest denominator.
(The largest denominator is 16.)
MD0802
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