Subtract 12/21 from 21/30
21/30 - 12/21 is 9/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
12/21 = 12 × 10/21 × 10 = 120/210 - Subtract the two like fractions:
147/210 - 120/210 = 147 - 120/210 = 27/210 - After reducing the fraction, the answer is 9/70
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