Subtract 81/42 from 15/2
1st number: 7 1/2, 2nd number: 1 39/42
15/2 - 81/42 is 39/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 2 × 21 = 42,
15/2 = 15 × 21/2 × 21 = 315/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
81/42 = 81 × 1/42 × 1 = 81/42 - Subtract the two like fractions:
315/42 - 81/42 = 315 - 81/42 = 234/42 - After reducing the fraction, the answer is 39/7
- In mixed form: 54/7
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