Subtract 20/70 from 3/84
3/84 - 20/70 is -1/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 70 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 70 × 6 = 420,
20/70 = 20 × 6/70 × 6 = 120/420 - Subtract the two like fractions:
15/420 - 120/420 = 15 - 120/420 = -105/420 - After reducing the fraction, the answer is -1/4
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