Add 21/18 and 18/24, Solve 1 3/18 + 18/24 as a fraction

Add 21/18 and 18/24

1^st number: 1 3/18, 2^nd number: 18/24

21/18 + 18/24 is 23/12.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 24 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 24 × 3 = 72,
18/24 = 18 × 3/24 × 3 = 54/72
Add the two like fractions:
84/72 + 54/72 = 84 + 54/72 = 138/72
138/72 simplified gives 23/12
So, 21/18 + 18/24 = 23/12
In mixed form: 111/12

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