Add 12/15 and 21/9
1st number: 12/15, 2nd number: 2 3/9
12/15 + 21/9 is 47/15.
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,
12/15 = 12 × 3/15 × 3 = 36/45 - Likewise, for the 2nd fraction, since 9 × 5 = 45,
21/9 = 21 × 5/9 × 5 = 105/45 - Add the two like fractions:
36/45 + 105/45 = 36 + 105/45 = 141/45 - 141/45 simplified gives 47/15
- So, 12/15 + 21/9 = 47/15
In mixed form: 32/15
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