Add 21/18 and 12/8
1st number: 1 3/18, 2nd number: 1 4/8
21/18 + 12/8 is 8/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
21/18 = 21 × 4/18 × 4 = 84/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
12/8 = 12 × 9/8 × 9 = 108/72 - Add the two like fractions:
84/72 + 108/72 = 84 + 108/72 = 192/72 - 192/72 simplified gives 8/3
- So, 21/18 + 12/8 = 8/3
In mixed form: 22/3
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