Subtract 8/20 from 30/84
30/84 - 8/20 is -3/70.
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,
30/84 = 30 × 5/84 × 5 = 150/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
8/20 = 8 × 21/20 × 21 = 168/420 - Subtract the two like fractions:
150/420 - 168/420 = 150 - 168/420 = -18/420 - After reducing the fraction, the answer is -3/70
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