Add 18/20 and 81/90
18/20 + 81/90 is 9/5.
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,
18/20 = 18 × 9/20 × 9 = 162/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
81/90 = 81 × 2/90 × 2 = 162/180 - Add the two like fractions:
162/180 + 162/180 = 162 + 162/180 = 324/180 - 324/180 simplified gives 9/5
- So, 18/20 + 81/90 = 9/5
In mixed form: 14/5
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