Subtract 21/42 from 72/54
1st number: 1 18/54, 2nd number: 21/42
72/54 - 21/42 is 5/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 42 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
72/54 = 72 × 7/54 × 7 = 504/378 - Likewise, for the 2nd fraction, since 42 × 9 = 378,
21/42 = 21 × 9/42 × 9 = 189/378 - Subtract the two like fractions:
504/378 - 189/378 = 504 - 189/378 = 315/378 - After reducing the fraction, the answer is 5/6
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