Subtract 21/18 from 12/16
1st number: 12/16, 2nd number: 1 3/18
12/16 - 21/18 is -5/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 16 and 18 is 144
Next, find the equivalent fraction of both fractional numbers with denominator 144 - For the 1st fraction, since 16 × 9 = 144,
12/16 = 12 × 9/16 × 9 = 108/144 - Likewise, for the 2nd fraction, since 18 × 8 = 144,
21/18 = 21 × 8/18 × 8 = 168/144 - Subtract the two like fractions:
108/144 - 168/144 = 108 - 168/144 = -60/144 - After reducing the fraction, the answer is -5/12
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