Subtract 42/9 from 81/20
1st number: 4 1/20, 2nd number: 4 6/9
81/20 - 42/9 is -37/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 9 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
81/20 = 81 × 9/20 × 9 = 729/180 - Likewise, for the 2nd fraction, since 9 × 20 = 180,
42/9 = 42 × 20/9 × 20 = 840/180 - Subtract the two like fractions:
729/180 - 840/180 = 729 - 840/180 = -111/180 - After reducing the fraction, the answer is -37/60
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