Add 21/3 and 15/21
1st number: 7 0/3, 2nd number: 15/21
21/3 + 15/21 is 54/7.
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,
21/3 = 21 × 7/3 × 7 = 147/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
15/21 = 15 × 1/21 × 1 = 15/21 - Add the two like fractions:
147/21 + 15/21 = 147 + 15/21 = 162/21 - 162/21 simplified gives 54/7
- So, 21/3 + 15/21 = 54/7
In mixed form: 75/7
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