Subtract 21/45 from 1/84
1/84 - 21/45 is -191/420.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 45 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 84 × 15 = 1260,
1/84 = 1 × 15/84 × 15 = 15/1260 - Likewise, for the 2nd fraction, since 45 × 28 = 1260,
21/45 = 21 × 28/45 × 28 = 588/1260 - Subtract the two like fractions:
15/1260 - 588/1260 = 15 - 588/1260 = -573/1260 - After reducing the fraction, the answer is -191/420
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