Subtract 81/21 from 15/2
1st number: 7 1/2, 2nd number: 3 18/21
15/2 - 81/21 is 51/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 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 21 × 2 = 42,
81/21 = 81 × 2/21 × 2 = 162/42 - Subtract the two like fractions:
315/42 - 162/42 = 315 - 162/42 = 153/42 - After reducing the fraction, the answer is 51/14
- In mixed form: 39/14
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