Answer:
4.1
Step-by-step explanation:
Divide 1.2 and 2.3
1/2 plus 1/3 is 5/6.
You have to find the common denominator
The equation for the direct variation is y= kx (where k is contant of variation.)
This equation represent that if x will increase then y will also increase because it's k times x.
Where the equation for indirect variation is 
By this equation if x will increase then y will decrease and vice versa.
The given data is :
x: 2 4 8 12
y: 4 2 1 2/3
Notice as x is increasing then y is decreasing. Like x has increased from 2 to 4 then y is decresing from 4 to 2 and so on.
So, the given data represent an indirect variation.
The correct unit for this triangle would be cm. Hope this helps!

Actually Welcome to the Concept of the Arithmetic Operation.
====> 5(3+6) + 5*3/ 5(4-1)
=====> 5(9) + 15 / 5(3)
=====> 45+15 / 15
=====> 60/15
======> 4
answer is 4