Add 21/45 and 70/81
21/45 + 70/81 is 539/405.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 45 × 9 = 405,
21/45 = 21 × 9/45 × 9 = 189/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
70/81 = 70 × 5/81 × 5 = 350/405 - Add the two like fractions:
189/405 + 350/405 = 189 + 350/405 = 539/405 - So, 21/45 + 70/81 = 539/405
In mixed form: 1134/405
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