Subtract 15/49 from 4/21
4/21 - 15/49 is -17/147.
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,
4/21 = 4 × 7/21 × 7 = 28/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
15/49 = 15 × 3/49 × 3 = 45/147 - Subtract the two like fractions:
28/147 - 45/147 = 28 - 45/147 = -17/147
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