Subtract 3/21 from 81/30
1st number: 2 21/30, 2nd number: 3/21
81/30 - 3/21 is 179/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
81/30 = 81 × 7/30 × 7 = 567/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
3/21 = 3 × 10/21 × 10 = 30/210 - Subtract the two like fractions:
567/210 - 30/210 = 567 - 30/210 = 537/210 - After reducing the fraction, the answer is 179/70
- In mixed form: 239/70
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