Subtract 45/30 from 8/21
1st number: 8/21, 2nd number: 1 15/30
8/21 - 45/30 is -47/42.
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,
8/21 = 8 × 10/21 × 10 = 80/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
45/30 = 45 × 7/30 × 7 = 315/210 - Subtract the two like fractions:
80/210 - 315/210 = 80 - 315/210 = -235/210 - After reducing the fraction, the answer is -47/42
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