Add 72/81 and 81/20
1st number: 72/81, 2nd number: 4 1/20
72/81 + 81/20 is 889/180.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 20 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 81 × 20 = 1620,
72/81 = 72 × 20/81 × 20 = 1440/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
81/20 = 81 × 81/20 × 81 = 6561/1620 - Add the two like fractions:
1440/1620 + 6561/1620 = 1440 + 6561/1620 = 8001/1620 - 8001/1620 simplified gives 889/180
- So, 72/81 + 81/20 = 889/180
In mixed form: 4169/180
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