Add 28/21 and 9/7
1st number: 1 7/21, 2nd number: 1 2/7
28/21 + 9/7 is 55/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
28/21 = 28 × 1/21 × 1 = 28/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
9/7 = 9 × 3/7 × 3 = 27/21 - Add the two like fractions:
28/21 + 27/21 = 28 + 27/21 = 55/21 - So, 28/21 + 9/7 = 55/21
In mixed form: 213/21
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