Add 15/3 and 12/21
1st number: 5 0/3, 2nd number: 12/21
15/3 + 12/21 is 39/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
15/3 = 15 × 7/3 × 7 = 105/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
12/21 = 12 × 1/21 × 1 = 12/21 - Add the two like fractions:
105/21 + 12/21 = 105 + 12/21 = 117/21 - 117/21 simplified gives 39/7
- So, 15/3 + 12/21 = 39/7
In mixed form: 54/7
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