Add 21/20 and 81/45
1st number: 1 1/20, 2nd number: 1 36/45
21/20 + 81/45 is 57/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
81/45 = 81 × 4/45 × 4 = 324/180 - Add the two like fractions:
189/180 + 324/180 = 189 + 324/180 = 513/180 - 513/180 simplified gives 57/20
- So, 21/20 + 81/45 = 57/20
In mixed form: 217/20
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