The answers to the questions
Answer:

--- Variance
Step-by-step explanation:
Given

Solving (a): Calculate the mean.
The given data is a grouped data. So, first we calculate the class midpoint (x)
For 51 - 58.

For 59 - 66

For 67 - 74

For 75 - 82

For 83 - 90

So, the table becomes:

The mean is then calculated as:



-- approximated
Solving (b): The sample variance:
This is calculated as:

So, we have:


-- approximated
Answer:
<h2>125 tickets for an adult</h2><h2>and 175 tickets for a student</h2>
Step-by-step explanation:


Answer:
<h2>3 g/cm³</h2>
Step-by-step explanation:
The density of a substance can be found by using the formula

From the question we have

We have the final answer as
<h3>3 g/cm³</h3>
Hope this helps you
Answer:
y =74x
Step-by-step explanation:
A proportional relationship is represented by y = kx where x is the independent variable, or input, k is the constant of proportionality, and y is the dependent variable or output.
What do we do to the values in the row for x to get the values in the row of y?
It helps to have x = 1 in this table.
74 = (k)(1)
74 = k