The x which achieve these statement is x=0.
Let n be the total number of puffs. Now we can write:

Adding the fractional value of n, we get:

Simplifying and rearranging gives us:

Therefore we can simplify to get:

and finally

The fraction of the puff that are tuna is found from:

As we know :
Dividend = Divisor × Quotient ( taking remainder as 0 )
So, Quotient = Dividend ÷ Divisor
by using the above relation we can say :
therefore, correct option is C. t ÷ 23
If it is a ratio of 3:5 you are dividing 480 into 8 parts (3+5).
So divide 480 by 8: 480/8 = 60
Then the ratio is (3x60):(5x60) or 180:300
To check it is correct, add up the two parts to see that they come to 480:
180+300 = 480. All good.
Hope this helps
If the question meant f(x)=2^(x) -3 then the answer should be 1 over 4 or 1/4