Subtract 21/81 from 42/50
42/50 - 21/81 is 392/675.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 81 is 4050
Next, find the equivalent fraction of both fractional numbers with denominator 4050 - For the 1st fraction, since 50 × 81 = 4050,
42/50 = 42 × 81/50 × 81 = 3402/4050 - Likewise, for the 2nd fraction, since 81 × 50 = 4050,
21/81 = 21 × 50/81 × 50 = 1050/4050 - Subtract the two like fractions:
3402/4050 - 1050/4050 = 3402 - 1050/4050 = 2352/4050 - After reducing the fraction, the answer is 392/675
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