Add 21/20 and 15/21
1st number: 1 1/20, 2nd number: 15/21
21/20 + 15/21 is 247/140.
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,
15/21 = 15 × 20/21 × 20 = 300/420 - Add the two like fractions:
441/420 + 300/420 = 441 + 300/420 = 741/420 - 741/420 simplified gives 247/140
- So, 21/20 + 15/21 = 247/140
In mixed form: 1107/140
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