Add 28/72 and 90/81
1st number: 28/72, 2nd number: 1 9/81
28/72 + 90/81 is 3/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 72 × 9 = 648,
28/72 = 28 × 9/72 × 9 = 252/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
90/81 = 90 × 8/81 × 8 = 720/648 - Add the two like fractions:
252/648 + 720/648 = 252 + 720/648 = 972/648 - 972/648 simplified gives 3/2
- So, 28/72 + 90/81 = 3/2
In mixed form: 11/2
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