Subtract 21/7 from 81/2
1st number: 40 1/2, 2nd number: 3 0/7
81/2 - 21/7 is 75/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 7 is 14
Next, find the equivalent fraction of both fractional numbers with denominator 14 - For the 1st fraction, since 2 × 7 = 14,
81/2 = 81 × 7/2 × 7 = 567/14 - Likewise, for the 2nd fraction, since 7 × 2 = 14,
21/7 = 21 × 2/7 × 2 = 42/14 - Subtract the two like fractions:
567/14 - 42/14 = 567 - 42/14 = 525/14 - After reducing the fraction, the answer is 75/2
- In mixed form: 371/2
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