Subtract 81/70 from 18/20
1st number: 18/20, 2nd number: 1 11/70
18/20 - 81/70 is -9/35.
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,
18/20 = 18 × 7/20 × 7 = 126/140 - Likewise, for the 2nd fraction, since 70 × 2 = 140,
81/70 = 81 × 2/70 × 2 = 162/140 - Subtract the two like fractions:
126/140 - 162/140 = 126 - 162/140 = -36/140 - After reducing the fraction, the answer is -9/35
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