Subtract 81/70 from 30/42
1st number: 30/42, 2nd number: 1 11/70
30/42 - 81/70 is -31/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
30/42 = 30 × 5/42 × 5 = 150/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
81/70 = 81 × 3/70 × 3 = 243/210 - Subtract the two like fractions:
150/210 - 243/210 = 150 - 243/210 = -93/210 - After reducing the fraction, the answer is -31/70
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