Subtract 21/7 from 1/2
1st number: 1/2, 2nd number: 3 0/7
1/2 - 21/7 is -5/2.
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,
1/2 = 1 × 7/2 × 7 = 7/14 - Likewise, for the 2nd fraction, since 7 × 2 = 14,
21/7 = 21 × 2/7 × 2 = 42/14 - Subtract the two like fractions:
7/14 - 42/14 = 7 - 42/14 = -35/14 - After reducing the fraction, the answer is -5/2
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