The given expression is:

$\frac{6}{4} + \sqrt{15}$

Simplifying:

1. Simplify $\frac{6}{4}$: $\frac{6}{4} = 1.5$

2. The expression becomes: $1.5 + \sqrt{15}$

Since $\sqrt{15}$ is an irrational number, its approximate value is: $\sqrt{15} \approx 3.872$

Final Answer:

$1.5 + 3.872 = 5.372$

Would you like further details or have any questions?

Here are 5 related questions:

1. What is the square root of other non-perfect squares, such as $\sqrt{14}$ or $\sqrt{17}$?
2. How do we handle irrational numbers in equations?
3. Can the square root of any non-perfect square be simplified?
4. What are the rules for combining rational and irrational numbers?
5. How do you simplify fractional expressions before adding them?

Tip: Always simplify fractions or surds before performing addition for cleaner results.