Subtract 81/21 from 15/30
1st number: 15/30, 2nd number: 3 18/21
15/30 - 81/21 is -47/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
15/30 = 15 × 7/30 × 7 = 105/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
81/21 = 81 × 10/21 × 10 = 810/210 - Subtract the two like fractions:
105/210 - 810/210 = 105 - 810/210 = -705/210 - After reducing the fraction, the answer is -47/14
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