Subtract 90/12 from 21/42
1st number: 21/42, 2nd number: 7 6/12
21/42 - 90/12 is -7/1.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
90/12 = 90 × 7/12 × 7 = 630/84 - Subtract the two like fractions:
42/84 - 630/84 = 42 - 630/84 = -588/84 - After reducing the fraction, the answer is -7/1
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