Subtract 45/21 from 72/84
1st number: 72/84, 2nd number: 2 3/21
72/84 - 45/21 is -9/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
72/84 = 72 × 1/84 × 1 = 72/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
45/21 = 45 × 4/21 × 4 = 180/84 - Subtract the two like fractions:
72/84 - 180/84 = 72 - 180/84 = -108/84 - After reducing the fraction, the answer is -9/7
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