Subtract 9/5 from 81/42
1st number: 1 39/42, 2nd number: 1 4/5
81/42 - 9/5 is 9/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 5 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 5 × 42 = 210,
9/5 = 9 × 42/5 × 42 = 378/210 - Subtract the two like fractions:
405/210 - 378/210 = 405 - 378/210 = 27/210 - After reducing the fraction, the answer is 9/70
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