Add 7/72 and 21/81
7/72 + 21/81 is 77/216.
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,
7/72 = 7 × 9/72 × 9 = 63/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
21/81 = 21 × 8/81 × 8 = 168/648 - Add the two like fractions:
63/648 + 168/648 = 63 + 168/648 = 231/648 - 231/648 simplified gives 77/216
- So, 7/72 + 21/81 = 77/216
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