Add 21/9 and 72/20
1st number: 2 3/9, 2nd number: 3 12/20
21/9 + 72/20 is 89/15.
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,
72/20 = 72 × 9/20 × 9 = 648/180 - Add the two like fractions:
420/180 + 648/180 = 420 + 648/180 = 1068/180 - 1068/180 simplified gives 89/15
- So, 21/9 + 72/20 = 89/15
In mixed form: 514/15
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