Subtract 42/12 from 90/28
1st number: 3 6/28, 2nd number: 3 6/12
90/28 - 42/12 is -2/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
90/28 = 90 × 3/28 × 3 = 270/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
42/12 = 42 × 7/12 × 7 = 294/84 - Subtract the two like fractions:
270/84 - 294/84 = 270 - 294/84 = -24/84 - After reducing the fraction, the answer is -2/7
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