Subtract 81/42 from 15/10
1st number: 1 5/10, 2nd number: 1 39/42
15/10 - 81/42 is -3/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
15/10 = 15 × 21/10 × 21 = 315/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210 - Subtract the two like fractions:
315/210 - 405/210 = 315 - 405/210 = -90/210 - After reducing the fraction, the answer is -3/7
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