Add 21/12 and 18/24, Solve 1 9/12 + 18/24 as a fraction

Add 21/12 and 18/24

1^st number: 1 9/12, 2^nd number: 18/24

21/12 + 18/24 is 5/2.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 24 is 24

Next, find the equivalent fraction of both fractional numbers with denominator 24
For the 1st fraction, since 12 × 2 = 24,
21/12 = 21 × 2/12 × 2 = 42/24
Likewise, for the 2nd fraction, since 24 × 1 = 24,
18/24 = 18 × 1/24 × 1 = 18/24
Add the two like fractions:
42/24 + 18/24 = 42 + 18/24 = 60/24
60/24 simplified gives 5/2
So, 21/12 + 18/24 = 5/2
In mixed form: 21/2

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