Subtract 21/5 from 45/84
1st number: 45/84, 2nd number: 4 1/5
45/84 - 21/5 is -513/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 5 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
45/84 = 45 × 5/84 × 5 = 225/420 - Likewise, for the 2nd fraction, since 5 × 84 = 420,
21/5 = 21 × 84/5 × 84 = 1764/420 - Subtract the two like fractions:
225/420 - 1764/420 = 225 - 1764/420 = -1539/420 - After reducing the fraction, the answer is -513/140
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