Add 21/84 and 9/7
1st number: 21/84, 2nd number: 1 2/7
21/84 + 9/7 is 43/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 7 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
21/84 = 21 × 1/84 × 1 = 21/84 - Likewise, for the 2nd fraction, since 7 × 12 = 84,
9/7 = 9 × 12/7 × 12 = 108/84 - Add the two like fractions:
21/84 + 108/84 = 21 + 108/84 = 129/84 - 129/84 simplified gives 43/28
- So, 21/84 + 9/7 = 43/28
In mixed form: 115/28
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