Subtract 21/84 from 3/20
3/20 - 21/84 is -1/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
3/20 = 3 × 21/20 × 21 = 63/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Subtract the two like fractions:
63/420 - 105/420 = 63 - 105/420 = -42/420 - After reducing the fraction, the answer is -1/10
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