Add 30/72 and 21/81
30/72 + 21/81 is 73/108.
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,
30/72 = 30 × 9/72 × 9 = 270/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
21/81 = 21 × 8/81 × 8 = 168/648 - Add the two like fractions:
270/648 + 168/648 = 270 + 168/648 = 438/648 - 438/648 simplified gives 73/108
- So, 30/72 + 21/81 = 73/108
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