Add 18/72 and 21/81
18/72 + 21/81 is 55/108.
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,
18/72 = 18 × 9/72 × 9 = 162/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
21/81 = 21 × 8/81 × 8 = 168/648 - Add the two like fractions:
162/648 + 168/648 = 162 + 168/648 = 330/648 - 330/648 simplified gives 55/108
- So, 18/72 + 21/81 = 55/108
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