Add 21/90 and 15/12
1st number: 21/90, 2nd number: 1 3/12
21/90 + 15/12 is 89/60.
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,
21/90 = 21 × 2/90 × 2 = 42/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
15/12 = 15 × 15/12 × 15 = 225/180 - Add the two like fractions:
42/180 + 225/180 = 42 + 225/180 = 267/180 - 267/180 simplified gives 89/60
- So, 21/90 + 15/12 = 89/60
In mixed form: 129/60
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