Subtract 20/70 from 8/84
8/84 - 20/70 is -4/21.
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,
8/84 = 8 × 5/84 × 5 = 40/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
20/70 = 20 × 6/70 × 6 = 120/420 - Subtract the two like fractions:
40/420 - 120/420 = 40 - 120/420 = -80/420 - After reducing the fraction, the answer is -4/21
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