Add 12/20 and 81/90
12/20 + 81/90 is 3/2.
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,
12/20 = 12 × 9/20 × 9 = 108/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
81/90 = 81 × 2/90 × 2 = 162/180 - Add the two like fractions:
108/180 + 162/180 = 108 + 162/180 = 270/180 - 270/180 simplified gives 3/2
- So, 12/20 + 81/90 = 3/2
In mixed form: 11/2
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