Subtract 72/81 from 81/30
1st number: 2 21/30, 2nd number: 72/81
81/30 - 72/81 is 163/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 30 × 27 = 810,
81/30 = 81 × 27/30 × 27 = 2187/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
72/81 = 72 × 10/81 × 10 = 720/810 - Subtract the two like fractions:
2187/810 - 720/810 = 2187 - 720/810 = 1467/810 - After reducing the fraction, the answer is 163/90
- In mixed form: 173/90
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