Add 20/9 and 45/21
1st number: 2 2/9, 2nd number: 2 3/21
20/9 + 45/21 is 275/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
20/9 = 20 × 7/9 × 7 = 140/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
45/21 = 45 × 3/21 × 3 = 135/63 - Add the two like fractions:
140/63 + 135/63 = 140 + 135/63 = 275/63 - So, 20/9 + 45/21 = 275/63
In mixed form: 423/63
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