Add 28/30 and 21/90
28/30 + 21/90 is 7/6.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
28/30 = 28 × 3/30 × 3 = 84/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Add the two like fractions:
84/90 + 21/90 = 84 + 21/90 = 105/90 - 105/90 simplified gives 7/6
- So, 28/30 + 21/90 = 7/6
In mixed form: 11/6
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