Add 12/15 and 21/27
12/15 + 21/27 is 71/45.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 27 is 135
Next, find the equivalent fraction of both fractional numbers with denominator 135 - For the 1st fraction, since 15 × 9 = 135,
12/15 = 12 × 9/15 × 9 = 108/135 - Likewise, for the 2nd fraction, since 27 × 5 = 135,
21/27 = 21 × 5/27 × 5 = 105/135 - Add the two like fractions:
108/135 + 105/135 = 108 + 105/135 = 213/135 - 213/135 simplified gives 71/45
- So, 12/15 + 21/27 = 71/45
In mixed form: 126/45
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