Subtract 10/12 from 21/30
21/30 - 10/12 is -2/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 12 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 30 × 2 = 60,
21/30 = 21 × 2/30 × 2 = 42/60 - Likewise, for the 2nd fraction, since 12 × 5 = 60,
10/12 = 10 × 5/12 × 5 = 50/60 - Subtract the two like fractions:
42/60 - 50/60 = 42 - 50/60 = -8/60 - After reducing the fraction, the answer is -2/15
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