Subtract 12/9 from 21/70
1st number: 21/70, 2nd number: 1 3/9
21/70 - 12/9 is -31/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 9 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630 - Likewise, for the 2nd fraction, since 9 × 70 = 630,
12/9 = 12 × 70/9 × 70 = 840/630 - Subtract the two like fractions:
189/630 - 840/630 = 189 - 840/630 = -651/630 - After reducing the fraction, the answer is -31/30
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