Subtract 2/20 from 81/21
1st number: 3 18/21, 2nd number: 2/20
81/21 - 2/20 is 263/70.
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,
2/20 = 2 × 21/20 × 21 = 42/420 - Subtract the two like fractions:
1620/420 - 42/420 = 1620 - 42/420 = 1578/420 - After reducing the fraction, the answer is 263/70
- In mixed form: 353/70
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