Answer:
1.8
Step-by-step explanation:

It would be D because the division symbol represents subtraction when your expanding a fraction like this one. Hope that helped.
Answer:
E (Y) = 3
Step-by-step explanation:
If a 4-sided die is being rolled repeatedly; and the odd-numbered rolls (1st 3rd,5th, etc.)
The probability of odd number roll will be, p(T) = 
However, on your even-numbered rolls, you are victorious if you get a 3 or 4. Also, the probability of even number roll, p(U) = 
In order to calculate: E (Y); We can say Y to be the number of times you roll.
We know that;
E (Y) = E ( Y|T ) p(T) + E ( Y|U ) p(U)
Let us calculate E ( Y|T ) and E ( Y|U )
Y|T ≅ geometric = 
Y|U ≅ geometric = 
also; x ≅ geometric (p)
∴ E (x) =
⇒
= 4 ; also
= 2
E (Y) = 4 ×
+ 2 ×
= 2+1
E (Y) = 3
Answer:
7.2224
Step-by-step explanation:
The value of the summation is given by the formula ...
Sn = (a1)(1 -r^n)/(1 -r) . . . . . where a1 is the first of n terms, and r is the common ratio.
Your sum has first term and ratio ...
a1 = 2(0.6) . . . . . summation term for n=1
r = 0.6
So the sum is ...

Then the value of the entire given expression is ...

_____
A calculator can help you find the value.