Subtract 15/7 from 81/30
1st number: 2 21/30, 2nd number: 2 1/7
81/30 - 15/7 is 39/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 7 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 7 × 30 = 210,
15/7 = 15 × 30/7 × 30 = 450/210 - Subtract the two like fractions:
567/210 - 450/210 = 567 - 450/210 = 117/210 - After reducing the fraction, the answer is 39/70
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