To determine whether each sum is rational or irrational without calculating, we can analyze the components of each expression.
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The first sum is \( \frac{2}{1} + \frac{1}{7} + \frac{3}{5} \).
- All of these numbers are rational since they can be expressed as fractions (where the numerator and the denominator are both integers).
- The sum of rational numbers is always rational.
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The second sum is \( \pi + 9 \).
- Here, \( \pi \) is an irrational number and 9 is a rational number.
- The sum of a rational number and an irrational number is always irrational.
In conclusion:
- The first sum \( \frac{2}{1} + \frac{1}{7} + \frac{3}{5} \) is rational.
- The second sum \( \pi + 9 \) is irrational.