Subtract 90/30 from 81/42
1st number: 1 39/42, 2nd number: 3 0/30
81/42 - 90/30 is -15/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
90/30 = 90 × 7/30 × 7 = 630/210 - Subtract the two like fractions:
405/210 - 630/210 = 405 - 630/210 = -225/210 - After reducing the fraction, the answer is -15/14
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