Add 21/20 and 10/21
1st number: 1 1/20, 2nd number: 10/21
21/20 + 10/21 is 641/420.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
21/20 = 21 × 21/20 × 21 = 441/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
10/21 = 10 × 20/21 × 20 = 200/420 - Add the two like fractions:
441/420 + 200/420 = 441 + 200/420 = 641/420 - So, 21/20 + 10/21 = 641/420
In mixed form: 1221/420
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