Subtract 9/10 from 21/30
21/30 - 9/10 is -1/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 10 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 30 × 1 = 30,
21/30 = 21 × 1/30 × 1 = 21/30 - Likewise, for the 2nd fraction, since 10 × 3 = 30,
9/10 = 9 × 3/10 × 3 = 27/30 - Subtract the two like fractions:
21/30 - 27/30 = 21 - 27/30 = -6/30 - After reducing the fraction, the answer is -1/5
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