Subtract 81/21 from 18/10
1st number: 1 8/10, 2nd number: 3 18/21
18/10 - 81/21 is -72/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
18/10 = 18 × 21/10 × 21 = 378/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
81/21 = 81 × 10/21 × 10 = 810/210 - Subtract the two like fractions:
378/210 - 810/210 = 378 - 810/210 = -432/210 - After reducing the fraction, the answer is -72/35
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