Add 21/90 and 18/12
1st number: 21/90, 2nd number: 1 6/12
21/90 + 18/12 is 26/15.
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,
18/12 = 18 × 15/12 × 15 = 270/180 - Add the two like fractions:
42/180 + 270/180 = 42 + 270/180 = 312/180 - 312/180 simplified gives 26/15
- So, 21/90 + 18/12 = 26/15
In mixed form: 111/15
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