Subtract 7/15 from 81/42
1st number: 1 39/42, 2nd number: 7/15
81/42 - 7/15 is 307/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 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 15 × 14 = 210,
7/15 = 7 × 14/15 × 14 = 98/210 - Subtract the two like fractions:
405/210 - 98/210 = 405 - 98/210 = 307/210 - In mixed form: 197/210
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