Add 18/45 and 21/12
1st number: 18/45, 2nd number: 1 9/12
18/45 + 21/12 is 43/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 12 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
18/45 = 18 × 4/45 × 4 = 72/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
21/12 = 21 × 15/12 × 15 = 315/180 - Add the two like fractions:
72/180 + 315/180 = 72 + 315/180 = 387/180 - 387/180 simplified gives 43/20
- So, 18/45 + 21/12 = 43/20
In mixed form: 23/20
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