Subtract 21/63 from 12/45
12/45 - 21/63 is -1/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 63 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
12/45 = 12 × 7/45 × 7 = 84/315 - Likewise, for the 2nd fraction, since 63 × 5 = 315,
21/63 = 21 × 5/63 × 5 = 105/315 - Subtract the two like fractions:
84/315 - 105/315 = 84 - 105/315 = -21/315 - After reducing the fraction, the answer is -1/15
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