Subtract 18/6 from 81/21
1st number: 3 18/21, 2nd number: 3 0/6
81/21 - 18/6 is 6/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 6 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
81/21 = 81 × 2/21 × 2 = 162/42 - Likewise, for the 2nd fraction, since 6 × 7 = 42,
18/6 = 18 × 7/6 × 7 = 126/42 - Subtract the two like fractions:
162/42 - 126/42 = 162 - 126/42 = 36/42 - After reducing the fraction, the answer is 6/7
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