Subtract 81/42 from 20/25
1st number: 20/25, 2nd number: 1 39/42
20/25 - 81/42 is -79/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 42 is 1050
Next, find the equivalent fraction of both fractional numbers with denominator 1050 - For the 1st fraction, since 25 × 42 = 1050,
20/25 = 20 × 42/25 × 42 = 840/1050 - Likewise, for the 2nd fraction, since 42 × 25 = 1050,
81/42 = 81 × 25/42 × 25 = 2025/1050 - Subtract the two like fractions:
840/1050 - 2025/1050 = 840 - 2025/1050 = -1185/1050 - After reducing the fraction, the answer is -79/70
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