Subtract 7/20 from 6/21
6/21 - 7/20 is -9/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
6/21 = 6 × 20/21 × 20 = 120/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
7/20 = 7 × 21/20 × 21 = 147/420 - Subtract the two like fractions:
120/420 - 147/420 = 120 - 147/420 = -27/420 - After reducing the fraction, the answer is -9/140
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