Subtract 3/20 from 81/7
1st number: 11 4/7, 2nd number: 3/20
81/7 - 3/20 is 1599/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 7 × 20 = 140,
81/7 = 81 × 20/7 × 20 = 1620/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
3/20 = 3 × 7/20 × 7 = 21/140 - Subtract the two like fractions:
1620/140 - 21/140 = 1620 - 21/140 = 1599/140 - In mixed form: 1159/140
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