Subtract 42/81 from 25/50
25/50 - 42/81 is -1/54.
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,
25/50 = 25 × 81/50 × 81 = 2025/4050 - Likewise, for the 2nd fraction, since 81 × 50 = 4050,
42/81 = 42 × 50/81 × 50 = 2100/4050 - Subtract the two like fractions:
2025/4050 - 2100/4050 = 2025 - 2100/4050 = -75/4050 - After reducing the fraction, the answer is -1/54
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