Add 21/4 and 20/21
1st number: 5 1/4, 2nd number: 20/21
21/4 + 20/21 is 521/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
21/4 = 21 × 21/4 × 21 = 441/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Add the two like fractions:
441/84 + 80/84 = 441 + 80/84 = 521/84 - So, 21/4 + 20/21 = 521/84
In mixed form: 617/84
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