Subtract 21/54 from 42/84
42/84 - 21/54 is 1/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 54 is 756
Next, find the equivalent fraction of both fractional numbers with denominator 756 - For the 1st fraction, since 84 × 9 = 756,
42/84 = 42 × 9/84 × 9 = 378/756 - Likewise, for the 2nd fraction, since 54 × 14 = 756,
21/54 = 21 × 14/54 × 14 = 294/756 - Subtract the two like fractions:
378/756 - 294/756 = 378 - 294/756 = 84/756 - After reducing the fraction, the answer is 1/9
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