Add 21/12 and 42/24
1st number: 1 9/12, 2nd number: 1 18/24
21/12 + 42/24 is 7/2.
Steps for adding fractions
- 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,
42/24 = 42 × 1/24 × 1 = 42/24 - Add the two like fractions:
42/24 + 42/24 = 42 + 42/24 = 84/24 - 84/24 simplified gives 7/2
- So, 21/12 + 42/24 = 7/2
In mixed form: 31/2
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