I don't think when this number is added to any other rational number would produce an irrational number
But we do know that when 0.4 is added to an irrational number it would be irrational.
e.g; 0.4 + pi is irrational, etc, etc
So any other irrational number would make it irrational
Answer: 
Step-by-step explanation:
Given
The price of the ticket prior to match day is 
It is stated that there is
the markup on match day i.e.
The selling price of the ticket is

So, han must expect to pay
on that day
Answer:
21.73
Step-by-step explanation:
calculator
Step-by-step explanation:
the slope of a line is the ratio y/x.
that means when going from one point to the other, how many units is y changing, when x changes a certain number of units.
so, going from one point to the other here, x changes by 30 units (from -12 to +18). and y changes 15 units (from -9 to 6).
therefore, the slope is
15/30 = 1/2