Subtract 21/36 from 1/28
1/28 - 21/36 is -23/42.
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,
1/28 = 1 × 9/28 × 9 = 9/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
21/36 = 21 × 7/36 × 7 = 147/252 - Subtract the two like fractions:
9/252 - 147/252 = 9 - 147/252 = -138/252 - After reducing the fraction, the answer is -23/42
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