Subtract 25/21 from 45/12
1st number: 3 9/12, 2nd number: 1 4/21
45/12 - 25/21 is 215/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
45/12 = 45 × 7/12 × 7 = 315/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
25/21 = 25 × 4/21 × 4 = 100/84 - Subtract the two like fractions:
315/84 - 100/84 = 315 - 100/84 = 215/84 - In mixed form: 247/84
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