Subtract 28/70 from 81/30
1st number: 2 21/30, 2nd number: 28/70
81/30 - 28/70 is 23/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 70 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 70 × 3 = 210,
28/70 = 28 × 3/70 × 3 = 84/210 - Subtract the two like fractions:
567/210 - 84/210 = 567 - 84/210 = 483/210 - After reducing the fraction, the answer is 23/10
- In mixed form: 23/10
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