Subtract 30/49 from 12/21
12/21 - 30/49 is -2/49.
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,
12/21 = 12 × 7/21 × 7 = 84/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
30/49 = 30 × 3/49 × 3 = 90/147 - Subtract the two like fractions:
84/147 - 90/147 = 84 - 90/147 = -6/147 - After reducing the fraction, the answer is -2/49
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