Subtract 81/30 from 21/10
1st number: 2 1/10, 2nd number: 2 21/30
21/10 - 81/30 is -3/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 30 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 10 × 3 = 30,
21/10 = 21 × 3/10 × 3 = 63/30 - Likewise, for the 2nd fraction, since 30 × 1 = 30,
81/30 = 81 × 1/30 × 1 = 81/30 - Subtract the two like fractions:
63/30 - 81/30 = 63 - 81/30 = -18/30 - After reducing the fraction, the answer is -3/5
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