Subtract 81/70 from 12/42
1st number: 12/42, 2nd number: 1 11/70
12/42 - 81/70 is -61/70.
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,
12/42 = 12 × 5/42 × 5 = 60/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
81/70 = 81 × 3/70 × 3 = 243/210 - Subtract the two like fractions:
60/210 - 243/210 = 60 - 243/210 = -183/210 - After reducing the fraction, the answer is -61/70
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