Add 21/15 and 81/84
1st number: 1 6/15, 2nd number: 81/84
21/15 + 81/84 is 331/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 15 × 28 = 420,
21/15 = 21 × 28/15 × 28 = 588/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
81/84 = 81 × 5/84 × 5 = 405/420 - Add the two like fractions:
588/420 + 405/420 = 588 + 405/420 = 993/420 - 993/420 simplified gives 331/140
- So, 21/15 + 81/84 = 331/140
In mixed form: 251/140
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