Subtract 21/42 from 4/8
4/8 - 21/42 is 0/1.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 42 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
4/8 = 4 × 21/8 × 21 = 84/168 - Likewise, for the 2nd fraction, since 42 × 4 = 168,
21/42 = 21 × 4/42 × 4 = 84/168 - Subtract the two like fractions:
84/168 - 84/168 = 84 - 84/168 = 0/168 - The answer is 0
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