Subtract 18/5 from 21/84
1st number: 21/84, 2nd number: 3 3/5
21/84 - 18/5 is -67/20.
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,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 5 × 84 = 420,
18/5 = 18 × 84/5 × 84 = 1512/420 - Subtract the two like fractions:
105/420 - 1512/420 = 105 - 1512/420 = -1407/420 - After reducing the fraction, the answer is -67/20
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