Subtract 81/20 from 7/9
1st number: 7/9, 2nd number: 4 1/20
7/9 - 81/20 is -589/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 9 × 20 = 180,
7/9 = 7 × 20/9 × 20 = 140/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
81/20 = 81 × 9/20 × 9 = 729/180 - Subtract the two like fractions:
140/180 - 729/180 = 140 - 729/180 = -589/180
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