Subtract 42/12 from 90/84
1st number: 1 6/84, 2nd number: 3 6/12
90/84 - 42/12 is -17/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
90/84 = 90 × 1/84 × 1 = 90/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
42/12 = 42 × 7/12 × 7 = 294/84 - Subtract the two like fractions:
90/84 - 294/84 = 90 - 294/84 = -204/84 - After reducing the fraction, the answer is -17/7
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