Subtract 18/70 from 81/20
1st number: 4 1/20, 2nd number: 18/70
81/20 - 18/70 is 531/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 70 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
81/20 = 81 × 7/20 × 7 = 567/140 - Likewise, for the 2nd fraction, since 70 × 2 = 140,
18/70 = 18 × 2/70 × 2 = 36/140 - Subtract the two like fractions:
567/140 - 36/140 = 567 - 36/140 = 531/140 - In mixed form: 3111/140
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