Subtract 25/30 from 12/21
12/21 - 25/30 is -11/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
12/21 = 12 × 10/21 × 10 = 120/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
25/30 = 25 × 7/30 × 7 = 175/210 - Subtract the two like fractions:
120/210 - 175/210 = 120 - 175/210 = -55/210 - After reducing the fraction, the answer is -11/42
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