Subtract 21/10 from 12/30
1st number: 12/30, 2nd number: 2 1/10
12/30 - 21/10 is -17/10.
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,
12/30 = 12 × 1/30 × 1 = 12/30 - Likewise, for the 2nd fraction, since 10 × 3 = 30,
21/10 = 21 × 3/10 × 3 = 63/30 - Subtract the two like fractions:
12/30 - 63/30 = 12 - 63/30 = -51/30 - After reducing the fraction, the answer is -17/10
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