Subtract 21/81 from 7/2
1st number: 3 1/2, 2nd number: 21/81
7/2 - 21/81 is 175/54.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 81 is 162
Next, find the equivalent fraction of both fractional numbers with denominator 162 - For the 1st fraction, since 2 × 81 = 162,
7/2 = 7 × 81/2 × 81 = 567/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
21/81 = 21 × 2/81 × 2 = 42/162 - Subtract the two like fractions:
567/162 - 42/162 = 567 - 42/162 = 525/162 - After reducing the fraction, the answer is 175/54
- In mixed form: 313/54
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