Subtract 81/70 from 9/20
1st number: 9/20, 2nd number: 1 11/70
9/20 - 81/70 is -99/140.
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,
9/20 = 9 × 7/20 × 7 = 63/140 - Likewise, for the 2nd fraction, since 70 × 2 = 140,
81/70 = 81 × 2/70 × 2 = 162/140 - Subtract the two like fractions:
63/140 - 162/140 = 63 - 162/140 = -99/140
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