Subtract 20/81 from 42/8
1st number: 5 2/8, 2nd number: 20/81
42/8 - 20/81 is 1621/324.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 8 × 81 = 648,
42/8 = 42 × 81/8 × 81 = 3402/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
20/81 = 20 × 8/81 × 8 = 160/648 - Subtract the two like fractions:
3402/648 - 160/648 = 3402 - 160/648 = 3242/648 - After reducing the fraction, the answer is 1621/324
- In mixed form: 51/324
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