23 counting numbers less than 500 are square numbers
Answer:

Step-by-step explanation:
The fish population after t years can be modeled by the following equation:

In which F(0) is the initial population and r is the constant rate of decay.
Year one the fish population was 18000
This means that 
In year three the fish population was 8000 fish.
Two years later, so 






So

Answer:
an = 4/3n - 13/3.
Step-by-step explanation:
The first term is a1,
a24 = a1 + 23d
83/3 = a1 + 4/3* 23
a1 = 83/3 - 92/3
a1 = -9/3 = -3.
So the nth term an = -3 + 4/3(n - 1)
an = -3 + 4/3 n - 4/3
an = 4/3n - 13/3
Answer:
150 mL
Step-by-step explanation:
Let x represent the quantity of 75% solution needed. The total amount of alcohol in the 60% mixture will be ...
75%·x + 10%·45 = 60%·(x+45) . . . . . there will be x+45 mL of solution in the end
0.15x = 22.5 . . . . . . . . . . . . . . . . . . . . simplify, subtract .60x+4.5
22.5/0.15 = x = 150 . . . . . . . . . . . . . . mL of 75% solution needed
You will need 150 mL of the 75% solution.