Subtract 12/20 from 3/84
3/84 - 12/20 is -79/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
3/84 = 3 × 5/84 × 5 = 15/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
12/20 = 12 × 21/20 × 21 = 252/420 - Subtract the two like fractions:
15/420 - 252/420 = 15 - 252/420 = -237/420 - After reducing the fraction, the answer is -79/140
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