Subtract 21/9 from 12/8
1st number: 1 4/8, 2nd number: 2 3/9
12/8 - 21/9 is -5/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 9 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 8 × 9 = 72,
12/8 = 12 × 9/8 × 9 = 108/72 - Likewise, for the 2nd fraction, since 9 × 8 = 72,
21/9 = 21 × 8/9 × 8 = 168/72 - Subtract the two like fractions:
108/72 - 168/72 = 108 - 168/72 = -60/72 - After reducing the fraction, the answer is -5/6
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