Add 20/3 and 30/21
1st number: 6 2/3, 2nd number: 1 9/21
20/3 + 30/21 is 170/21.
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,
20/3 = 20 × 7/3 × 7 = 140/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
30/21 = 30 × 1/21 × 1 = 30/21 - Add the two like fractions:
140/21 + 30/21 = 140 + 30/21 = 170/21 - So, 20/3 + 30/21 = 170/21
In mixed form: 82/21
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