Subtract 9/12 from 21/70
21/70 - 9/12 is -9/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 12 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 70 × 6 = 420,
21/70 = 21 × 6/70 × 6 = 126/420 - Likewise, for the 2nd fraction, since 12 × 35 = 420,
9/12 = 9 × 35/12 × 35 = 315/420 - Subtract the two like fractions:
126/420 - 315/420 = 126 - 315/420 = -189/420 - After reducing the fraction, the answer is -9/20
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