Subtract 81/42 from 4/5
1st number: 4/5, 2nd number: 1 39/42
4/5 - 81/42 is -79/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 5 × 42 = 210,
4/5 = 4 × 42/5 × 42 = 168/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210 - Subtract the two like fractions:
168/210 - 405/210 = 168 - 405/210 = -237/210 - After reducing the fraction, the answer is -79/70
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