Subtract 28/49 from 5/21
5/21 - 28/49 is -1/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147
Next, find the equivalent fraction of both fractional numbers with denominator 147 - For the 1st fraction, since 21 × 7 = 147,
5/21 = 5 × 7/21 × 7 = 35/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
28/49 = 28 × 3/49 × 3 = 84/147 - Subtract the two like fractions:
35/147 - 84/147 = 35 - 84/147 = -49/147 - After reducing the fraction, the answer is -1/3
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