Subtract 21/45 from 8/21
8/21 - 21/45 is -3/35.
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,
8/21 = 8 × 15/21 × 15 = 120/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315 - Subtract the two like fractions:
120/315 - 147/315 = 120 - 147/315 = -27/315 - After reducing the fraction, the answer is -3/35
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