Add 15/90 and 21/12
1st number: 15/90, 2nd number: 1 9/12
15/90 + 21/12 is 23/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 12 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
15/90 = 15 × 2/90 × 2 = 30/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
21/12 = 21 × 15/12 × 15 = 315/180 - Add the two like fractions:
30/180 + 315/180 = 30 + 315/180 = 345/180 - 345/180 simplified gives 23/12
- So, 15/90 + 21/12 = 23/12
In mixed form: 111/12
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