Add 28/12 and 21/90
1st number: 2 4/12, 2nd number: 21/90
28/12 + 21/90 is 77/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 12 × 15 = 180,
28/12 = 28 × 15/12 × 15 = 420/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
21/90 = 21 × 2/90 × 2 = 42/180 - Add the two like fractions:
420/180 + 42/180 = 420 + 42/180 = 462/180 - 462/180 simplified gives 77/30
- So, 28/12 + 21/90 = 77/30
In mixed form: 217/30
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