Subtract 81/42 from 21/15
1st number: 1 6/15, 2nd number: 1 39/42
21/15 - 81/42 is -37/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 15 × 14 = 210,
21/15 = 21 × 14/15 × 14 = 294/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210 - Subtract the two like fractions:
294/210 - 405/210 = 294 - 405/210 = -111/210 - After reducing the fraction, the answer is -37/70
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