Subtract 30/45 from 6/21
6/21 - 30/45 is -8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
6/21 = 6 × 15/21 × 15 = 90/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
30/45 = 30 × 7/45 × 7 = 210/315 - Subtract the two like fractions:
90/315 - 210/315 = 90 - 210/315 = -120/315 - After reducing the fraction, the answer is -8/21
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