Subtract 81/24 from 42/20
1st number: 2 2/20, 2nd number: 3 9/24
42/20 - 81/24 is -51/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 24 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 20 × 6 = 120,
42/20 = 42 × 6/20 × 6 = 252/120 - Likewise, for the 2nd fraction, since 24 × 5 = 120,
81/24 = 81 × 5/24 × 5 = 405/120 - Subtract the two like fractions:
252/120 - 405/120 = 252 - 405/120 = -153/120 - After reducing the fraction, the answer is -51/40
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