Subtract 21/4 from 21/20
1st number: 1 1/20, 2nd number: 5 1/4
21/20 - 21/4 is -21/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 4 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 20 × 1 = 20,
21/20 = 21 × 1/20 × 1 = 21/20 - Likewise, for the 2nd fraction, since 4 × 5 = 20,
21/4 = 21 × 5/4 × 5 = 105/20 - Subtract the two like fractions:
21/20 - 105/20 = 21 - 105/20 = -84/20 - After reducing the fraction, the answer is -21/5
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