Subtract 8/84 from 81/21
1st number: 3 18/21, 2nd number: 8/84
81/21 - 8/84 is 79/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
81/21 = 81 × 4/21 × 4 = 324/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
8/84 = 8 × 1/84 × 1 = 8/84 - Subtract the two like fractions:
324/84 - 8/84 = 324 - 8/84 = 316/84 - After reducing the fraction, the answer is 79/21
- In mixed form: 316/21
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