Subtract 21/10 from 81/42
1st number: 1 39/42, 2nd number: 2 1/10
81/42 - 21/10 is -6/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 10 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 10 × 21 = 210,
21/10 = 21 × 21/10 × 21 = 441/210 - Subtract the two like fractions:
405/210 - 441/210 = 405 - 441/210 = -36/210 - After reducing the fraction, the answer is -6/35
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