To find the mean (average) of the numbers involved in the equation, we'll consider the values resulting from the summation process.

Step 1: Identify the Values

From the previous solution, we found that $y = 35$. The expression inside the summation is $y - 10$. Therefore, the value of the expression is:

$y - 10 = 35 - 10 = 25$

Since the summation runs from $i = 1$ to $i = 4$, the values being summed are all $25$ repeated 4 times.

Step 2: Calculate the Mean

To find the mean, you sum all the values and then divide by the number of values:

$\text{Mean} = \frac{25 + 25 + 25 + 25}{4} = \frac{100}{4} = 25$

Final Answer:

The mean of the values in the summation is 25.

Would you like more details or have any questions?

Here are 5 related questions to further explore:

1. How would the mean change if the summation involved different values for each $i$?
2. What is the mean if $y$ takes different values for each $i$?
3. How does the mean change if the number of terms in the summation increases?
4. What is the relationship between the mean and the sum of the values?
5. How does the mean of the results change if we alter the constant (e.g., $y - 15$ instead of $y - 10$)?

Tip: The mean is especially useful for understanding the central tendency of a set of numbers, providing insight into the overall "average" behavior of the data.