Subtract 18/21 from 12/4
1st number: 3 0/4, 2nd number: 18/21
12/4 - 18/21 is 15/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
12/4 = 12 × 21/4 × 21 = 252/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
18/21 = 18 × 4/21 × 4 = 72/84 - Subtract the two like fractions:
252/84 - 72/84 = 252 - 72/84 = 180/84 - After reducing the fraction, the answer is 15/7
- In mixed form: 21/7
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