Add 72/20 and 81/90
1st number: 3 12/20, 2nd number: 81/90
72/20 + 81/90 is 9/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
72/20 = 72 × 9/20 × 9 = 648/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
81/90 = 81 × 2/90 × 2 = 162/180 - Add the two like fractions:
648/180 + 162/180 = 648 + 162/180 = 810/180 - 810/180 simplified gives 9/2
- So, 72/20 + 81/90 = 9/2
In mixed form: 41/2
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