Subtract 72/10 from 81/30
1st number: 2 21/30, 2nd number: 7 2/10
81/30 - 72/10 is -9/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 10 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 30 × 1 = 30,
81/30 = 81 × 1/30 × 1 = 81/30 - Likewise, for the 2nd fraction, since 10 × 3 = 30,
72/10 = 72 × 3/10 × 3 = 216/30 - Subtract the two like fractions:
81/30 - 216/30 = 81 - 216/30 = -135/30 - After reducing the fraction, the answer is -9/2
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