Add 21/9 and 45/20
1st number: 2 3/9, 2nd number: 2 5/20
21/9 + 45/20 is 55/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 9 × 20 = 180,
21/9 = 21 × 20/9 × 20 = 420/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
45/20 = 45 × 9/20 × 9 = 405/180 - Add the two like fractions:
420/180 + 405/180 = 420 + 405/180 = 825/180 - 825/180 simplified gives 55/12
- So, 21/9 + 45/20 = 55/12
In mixed form: 47/12
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