Subtract 30/84 from 21/56
21/56 - 30/84 is 1/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 84 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
21/56 = 21 × 3/56 × 3 = 63/168 - Likewise, for the 2nd fraction, since 84 × 2 = 168,
30/84 = 30 × 2/84 × 2 = 60/168 - Subtract the two like fractions:
63/168 - 60/168 = 63 - 60/168 = 3/168 - After reducing the fraction, the answer is 1/56
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