Subtract 12/20 from 81/70
1st number: 1 11/70, 2nd number: 12/20
81/70 - 12/20 is 39/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 70 × 2 = 140,
81/70 = 81 × 2/70 × 2 = 162/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
12/20 = 12 × 7/20 × 7 = 84/140 - Subtract the two like fractions:
162/140 - 84/140 = 162 - 84/140 = 78/140 - After reducing the fraction, the answer is 39/70
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