then simplify the resulting fraction, if needed (or if you can). For example, 2/5 4/7
(2 4)/(5 7) 8/35 (this number can’t be simplified).
Division of fractions entails one main rule: You need to flip over, or invert, the
“divisor” fraction (the fraction on the bottom) to get the result (this is also called the
reciprocal of the fraction; see below). Here are the steps: First, change the division
sign to a multiplication sign after inverting the fraction to the right of the sign. Multi-
ply the numerators and denominators, and write the result. You can then simplify or
reduce the fraction if needed. For example, 1/2 1/4 1/2 4/1 4/2. This number
can be simplified to 2.
How are decimal fractionscalculated by adding, subtracting, multiplying
and dividing?
Decimal fractions are added, subtracted, multiplied and divided much like whole
numbers, but with decimal differences. The following gives some examples: Adding
such numbers as 0.3 0.2 is simple: 0.3 0.2 0.5. Adding whole and decimal frac-
tions is also easy: 2.4 5 7.4. These numbers are also easy to subtract, such as 0.3
0.2 0.1. Multiplication and division with fractions is also similar to doing so with
regular numbers, although the placement of the decimal point is all important. For
example, multiplying 24.45 0.002 0.0489; dividing the same numbers 24.45/.002
12,225. (It’s interesting to note here a “mathematical surprise”: In the last example,
dividing the small numbers equaled a much larger number—the opposite of what
most of us would expect.)
How do you reduce a fraction?
To reduce a fraction, there are three general steps: factor the numerator, factor the
denominator, and cancel out the fractional mixesthat have the value of one. The left-
over number is the reduced fraction. For example, to reduce 16/56, factor the numera-
tor (16 2 2 2 2) and factor the denominator (56 2 2 2 7); then
eliminate the 2s (2/2 equals 1):
The reduced fraction equals 2/7.
What do you calculate an equivalent fraction?
An equivalent fraction—also called “building fractions”—is the reverse of reducing
the fraction: Instead of searching for the 1 in the fractional mix that you can reduce,
you insert a 1 and build the fractions. For example, to find the equivalent fraction for
1/4, using the number 3, multiply the numerator and denominator by 3 (3/3 1); 1/4
56
16
2227
2222
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100
