Add 21/18 and 9/8
1st number: 1 3/18, 2nd number: 1 1/8
21/18 + 9/8 is 55/24.
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,
9/8 = 9 × 9/8 × 9 = 81/72 - Add the two like fractions:
84/72 + 81/72 = 84 + 81/72 = 165/72 - 165/72 simplified gives 55/24
- So, 21/18 + 9/8 = 55/24
In mixed form: 27/24
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