Add 18/3 and 15/21
1st number: 6 0/3, 2nd number: 15/21
18/3 + 15/21 is 47/7.
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,
18/3 = 18 × 7/3 × 7 = 126/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
15/21 = 15 × 1/21 × 1 = 15/21 - Add the two like fractions:
126/21 + 15/21 = 126 + 15/21 = 141/21 - 141/21 simplified gives 47/7
- So, 18/3 + 15/21 = 47/7
In mixed form: 65/7
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