Add 9/8 and 21/18, Solve 1 1/8 + 1 3/18 as a fraction

Add 9/8 and 21/18

1^st number: 1 1/8, 2^nd number: 1 3/18

9/8 + 21/18 is 55/24.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 18 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 8 × 9 = 72,
9/8 = 9 × 9/8 × 9 = 81/72
Likewise, for the 2nd fraction, since 18 × 4 = 72,
21/18 = 21 × 4/18 × 4 = 84/72
Add the two like fractions:
81/72 + 84/72 = 81 + 84/72 = 165/72
165/72 simplified gives 55/24
So, 9/8 + 21/18 = 55/24
In mixed form: 27/24

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