Subtract 30/8 from 21/12
1st number: 1 9/12, 2nd number: 3 6/8
21/12 - 30/8 is -2/1.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 8 is 24
Next, find the equivalent fraction of both fractional numbers with denominator 24 - For the 1st fraction, since 12 × 2 = 24,
21/12 = 21 × 2/12 × 2 = 42/24 - Likewise, for the 2nd fraction, since 8 × 3 = 24,
30/8 = 30 × 3/8 × 3 = 90/24 - Subtract the two like fractions:
42/24 - 90/24 = 42 - 90/24 = -48/24 - After reducing the fraction, the answer is -2/1
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