Add 21/12 and 15/8
1st number: 1 9/12, 2nd number: 1 7/8
21/12 + 15/8 is 29/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 8 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 8 × 3 = 24,
15/8 = 15 × 3/8 × 3 = 45/24 - Add the two like fractions:
42/24 + 45/24 = 42 + 45/24 = 87/24 - 87/24 simplified gives 29/8
- So, 21/12 + 15/8 = 29/8
In mixed form: 35/8
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