Subtract 30/36 from 21/28
21/28 - 30/36 is -1/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 28 × 9 = 252,
21/28 = 21 × 9/28 × 9 = 189/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
30/36 = 30 × 7/36 × 7 = 210/252 - Subtract the two like fractions:
189/252 - 210/252 = 189 - 210/252 = -21/252 - After reducing the fraction, the answer is -1/12
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