Add 12/15 and 21/45
12/15 + 21/45 is 19/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 45 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 45 × 1 = 45,
21/45 = 21 × 1/45 × 1 = 21/45 - Add the two like fractions:
36/45 + 21/45 = 36 + 21/45 = 57/45 - 57/45 simplified gives 19/15
- So, 12/15 + 21/45 = 19/15
In mixed form: 14/15
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