Subtract 18/42 from 81/30
1st number: 2 21/30, 2nd number: 18/42
81/30 - 18/42 is 159/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
81/30 = 81 × 7/30 × 7 = 567/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
18/42 = 18 × 5/42 × 5 = 90/210 - Subtract the two like fractions:
567/210 - 90/210 = 567 - 90/210 = 477/210 - After reducing the fraction, the answer is 159/70
- In mixed form: 219/70
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