Subtract 21/18 from 28/36
1st number: 28/36, 2nd number: 1 3/18
28/36 - 21/18 is -7/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 18 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 36 × 1 = 36,
28/36 = 28 × 1/36 × 1 = 28/36 - Likewise, for the 2nd fraction, since 18 × 2 = 36,
21/18 = 21 × 2/18 × 2 = 42/36 - Subtract the two like fractions:
28/36 - 42/36 = 28 - 42/36 = -14/36 - After reducing the fraction, the answer is -7/18
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