Subtract 14/20 from 12/21
12/21 - 14/20 is -9/70.
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,
12/21 = 12 × 20/21 × 20 = 240/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
14/20 = 14 × 21/20 × 21 = 294/420 - Subtract the two like fractions:
240/420 - 294/420 = 240 - 294/420 = -54/420 - After reducing the fraction, the answer is -9/70
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