Add 7/4 and 21/12
1st number: 1 3/4, 2nd number: 1 9/12
7/4 + 21/12 is 7/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 12 is 12
Next, find the equivalent fraction of both fractional numbers with denominator 12 - For the 1st fraction, since 4 × 3 = 12,
7/4 = 7 × 3/4 × 3 = 21/12 - Likewise, for the 2nd fraction, since 12 × 1 = 12,
21/12 = 21 × 1/12 × 1 = 21/12 - Add the two like fractions:
21/12 + 21/12 = 21 + 21/12 = 42/12 - 42/12 simplified gives 7/2
- So, 7/4 + 21/12 = 7/2
In mixed form: 31/2
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