Subtract 21/16 from 18/36
1st number: 18/36, 2nd number: 1 5/16
18/36 - 21/16 is -13/16.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 16 is 144
Next, find the equivalent fraction of both fractional numbers with denominator 144 - For the 1st fraction, since 36 × 4 = 144,
18/36 = 18 × 4/36 × 4 = 72/144 - Likewise, for the 2nd fraction, since 16 × 9 = 144,
21/16 = 21 × 9/16 × 9 = 189/144 - Subtract the two like fractions:
72/144 - 189/144 = 72 - 189/144 = -117/144 - After reducing the fraction, the answer is -13/16
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