Subtract 3/21 from 12/18
12/18 - 3/21 is 11/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
12/18 = 12 × 7/18 × 7 = 84/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
3/21 = 3 × 6/21 × 6 = 18/126 - Subtract the two like fractions:
84/126 - 18/126 = 84 - 18/126 = 66/126 - After reducing the fraction, the answer is 11/21
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