Subtract 45/21 from 42/12
1st number: 3 6/12, 2nd number: 2 3/21
42/12 - 45/21 is 19/14.
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,
42/12 = 42 × 7/12 × 7 = 294/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
45/21 = 45 × 4/21 × 4 = 180/84 - Subtract the two like fractions:
294/84 - 180/84 = 294 - 180/84 = 114/84 - After reducing the fraction, the answer is 19/14
- In mixed form: 15/14
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