Add 28/36 and 21/90
28/36 + 21/90 is 91/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 36 × 5 = 180,
28/36 = 28 × 5/36 × 5 = 140/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
21/90 = 21 × 2/90 × 2 = 42/180 - Add the two like fractions:
140/180 + 42/180 = 140 + 42/180 = 182/180 - 182/180 simplified gives 91/90
- So, 28/36 + 21/90 = 91/90
In mixed form: 11/90
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