Subtract 21/30 from 1/2
1/2 - 21/30 is -1/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 30 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 2 × 15 = 30,
1/2 = 1 × 15/2 × 15 = 15/30 - Likewise, for the 2nd fraction, since 30 × 1 = 30,
21/30 = 21 × 1/30 × 1 = 21/30 - Subtract the two like fractions:
15/30 - 21/30 = 15 - 21/30 = -6/30 - After reducing the fraction, the answer is -1/5
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