Subtract 81/30 from 90/42
1st number: 2 6/42, 2nd number: 2 21/30
90/42 - 81/30 is -39/70.
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,
90/42 = 90 × 5/42 × 5 = 450/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
81/30 = 81 × 7/30 × 7 = 567/210 - Subtract the two like fractions:
450/210 - 567/210 = 450 - 567/210 = -117/210 - After reducing the fraction, the answer is -39/70
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