2.5 because if you move x to the other side of the equation you will get y=2.5x, and the constant of proportionality is what x is multiplied by, in this case, it's 2.5.
Answer:

Step-by-step explanation:
Given

Let p represents the proportion of those who worry about identity theft;

Required
Mean of those who do not worry about identity theft
First, the proportion of those who do not worry, has to be calculated;
Represent this with q
In probability;

Make q the subject of formula

Substitute 

Convert percentage to fraction


Now, the mean can be calculated using:

Where n represents the population


(Approximated)
<span>Five Thousand ones equals Fifty hundred ones; this can be understood by moving the numerical comma on place 5,000 becomes 50,00; to change the notation you can also divide 5,000 by 100 which equals 50. Therefore it equals 50 hundred ones. By simple division you can arrive at the answer for this.</span>