Subtract 8/20 from 81/21
1st number: 3 18/21, 2nd number: 8/20
81/21 - 8/20 is 121/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
81/21 = 81 × 20/21 × 20 = 1620/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
8/20 = 8 × 21/20 × 21 = 168/420 - Subtract the two like fractions:
1620/420 - 168/420 = 1620 - 168/420 = 1452/420 - After reducing the fraction, the answer is 121/35
- In mixed form: 316/35
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