Add 20/84 and 21/9
1st number: 20/84, 2nd number: 2 3/9
20/84 + 21/9 is 18/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 9 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
20/84 = 20 × 3/84 × 3 = 60/252 - Likewise, for the 2nd fraction, since 9 × 28 = 252,
21/9 = 21 × 28/9 × 28 = 588/252 - Add the two like fractions:
60/252 + 588/252 = 60 + 588/252 = 648/252 - 648/252 simplified gives 18/7
- So, 20/84 + 21/9 = 18/7
In mixed form: 24/7
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