Subtract 42/5 from 21/84
1st number: 21/84, 2nd number: 8 2/5
21/84 - 42/5 is -163/20.
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,
42/5 = 42 × 84/5 × 84 = 3528/420 - Subtract the two like fractions:
105/420 - 3528/420 = 105 - 3528/420 = -3423/420 - After reducing the fraction, the answer is -163/20
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