Final answer:
The operation that results in a rational number is A. √25 + 0.7, as the square root of 25 is 5, and adding it to 0.7 gives us 5.7, which is a rational number.
Step-by-step explanation:
The question asks which operation results in a rational number. We can evaluate each operation:
- A. √25 + 0.7: √25 is 5, and when we add 0.7, we get 5.7, which is a rational number.
- B. (−√3)(−2): Since √3 is an irrational number, the product of it and any non-zero integer is still irrational.
- C. π + 1/4: π is irrational, and adding a rational number to an irrational number results in an irrational number.
- D. −−√6 × √3: The product involves two square roots, which may be irrational; however, if we calculate it, −−√6 × √3 equals √(6×3), which simplifies to √18. Since 18 is not a perfect square, the result is an irrational number.
Therefore, the operation that results in a rational number is A. √25 + 0.7.