Subtract 81/30 from 27/21
1st number: 1 6/21, 2nd number: 2 21/30
27/21 - 81/30 is -99/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
27/21 = 27 × 10/21 × 10 = 270/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
81/30 = 81 × 7/30 × 7 = 567/210 - Subtract the two like fractions:
270/210 - 567/210 = 270 - 567/210 = -297/210 - After reducing the fraction, the answer is -99/70
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