Subtract 18/49 from 1/21
1/21 - 18/49 is -47/147.
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,
1/21 = 1 × 7/21 × 7 = 7/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
18/49 = 18 × 3/49 × 3 = 54/147 - Subtract the two like fractions:
7/147 - 54/147 = 7 - 54/147 = -47/147
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