Add 21/15 and 18/81
1st number: 1 6/15, 2nd number: 18/81
21/15 + 18/81 is 73/45.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 15 × 27 = 405,
21/15 = 21 × 27/15 × 27 = 567/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
18/81 = 18 × 5/81 × 5 = 90/405 - Add the two like fractions:
567/405 + 90/405 = 567 + 90/405 = 657/405 - 657/405 simplified gives 73/45
- So, 21/15 + 18/81 = 73/45
In mixed form: 128/45
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