Add 81/18 and 72/20
1st number: 4 9/18, 2nd number: 3 12/20
81/18 + 72/20 is 81/10.
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,
81/18 = 81 × 10/18 × 10 = 810/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
72/20 = 72 × 9/20 × 9 = 648/180 - Add the two like fractions:
810/180 + 648/180 = 810 + 648/180 = 1458/180 - 1458/180 simplified gives 81/10
- So, 81/18 + 72/20 = 81/10
In mixed form: 81/10
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