Subtract 21/30 from 3/5
3/5 - 21/30 is -1/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 30 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 5 × 6 = 30,
3/5 = 3 × 6/5 × 6 = 18/30 - Likewise, for the 2nd fraction, since 30 × 1 = 30,
21/30 = 21 × 1/30 × 1 = 21/30 - Subtract the two like fractions:
18/30 - 21/30 = 18 - 21/30 = -3/30 - After reducing the fraction, the answer is -1/10
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