Subtract 30/7 from 81/42
1st number: 1 39/42, 2nd number: 4 2/7
81/42 - 30/7 is -33/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 7 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
81/42 = 81 × 1/42 × 1 = 81/42 - Likewise, for the 2nd fraction, since 7 × 6 = 42,
30/7 = 30 × 6/7 × 6 = 180/42 - Subtract the two like fractions:
81/42 - 180/42 = 81 - 180/42 = -99/42 - After reducing the fraction, the answer is -33/14
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