Subtract 90/21 from 15/36
1st number: 15/36, 2nd number: 4 6/21
15/36 - 90/21 is -325/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 21 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
15/36 = 15 × 7/36 × 7 = 105/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
90/21 = 90 × 12/21 × 12 = 1080/252 - Subtract the two like fractions:
105/252 - 1080/252 = 105 - 1080/252 = -975/252 - After reducing the fraction, the answer is -325/84
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