Subtract 21/54 from 42/30
1st number: 1 12/30, 2nd number: 21/54
42/30 - 21/54 is 91/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 54 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 30 × 9 = 270,
42/30 = 42 × 9/30 × 9 = 378/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
21/54 = 21 × 5/54 × 5 = 105/270 - Subtract the two like fractions:
378/270 - 105/270 = 378 - 105/270 = 273/270 - After reducing the fraction, the answer is 91/90
- In mixed form: 11/90
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