Subtract 21/84 from 20/45
20/45 - 21/84 is 7/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 84 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 45 × 28 = 1260,
20/45 = 20 × 28/45 × 28 = 560/1260 - Likewise, for the 2nd fraction, since 84 × 15 = 1260,
21/84 = 21 × 15/84 × 15 = 315/1260 - Subtract the two like fractions:
560/1260 - 315/1260 = 560 - 315/1260 = 245/1260 - After reducing the fraction, the answer is 7/36
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