Answer:
40/9
Step-by-step explanation:
You can write 1 4/5 as an improper fraction which is
. 8÷
is the same as
which is 
Teh probability that the first marble is blue is 6/16
teh second being red is 10/15
so multiply them
and u get 1/4
d + 8 = 1/4(x-9)
d + 8 = 1/4x - 9/4
- 8 - 8
------------------------------
d = 1/4x - 17
I just realized that this is not the answer you are looking for. It's an equation, not a value. Sorry about that.
I would say 10 if it is an exponent