Subtract 81/70 from 20/30
1st number: 20/30, 2nd number: 1 11/70
20/30 - 81/70 is -103/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
20/30 = 20 × 7/30 × 7 = 140/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
81/70 = 81 × 3/70 × 3 = 243/210 - Subtract the two like fractions:
140/210 - 243/210 = 140 - 243/210 = -103/210
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