Add 72/18 and 81/20
1st number: 4 0/18, 2nd number: 4 1/20
72/18 + 81/20 is 161/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 18 × 10 = 180,
72/18 = 72 × 10/18 × 10 = 720/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
81/20 = 81 × 9/20 × 9 = 729/180 - Add the two like fractions:
720/180 + 729/180 = 720 + 729/180 = 1449/180 - 1449/180 simplified gives 161/20
- So, 72/18 + 81/20 = 161/20
In mixed form: 81/20
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