Subtract 21/5 from 81/4
1st number: 20 1/4, 2nd number: 4 1/5
81/4 - 21/5 is 321/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 5 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 4 × 5 = 20,
81/4 = 81 × 5/4 × 5 = 405/20 - Likewise, for the 2nd fraction, since 5 × 4 = 20,
21/5 = 21 × 4/5 × 4 = 84/20 - Subtract the two like fractions:
405/20 - 84/20 = 405 - 84/20 = 321/20 - In mixed form: 161/20
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