Add 28/15 and 21/9
1st number: 1 13/15, 2nd number: 2 3/9
28/15 + 21/9 is 21/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 9 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 15 × 3 = 45,
28/15 = 28 × 3/15 × 3 = 84/45 - Likewise, for the 2nd fraction, since 9 × 5 = 45,
21/9 = 21 × 5/9 × 5 = 105/45 - Add the two like fractions:
84/45 + 105/45 = 84 + 105/45 = 189/45 - 189/45 simplified gives 21/5
- So, 28/15 + 21/9 = 21/5
In mixed form: 41/5
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