<h2><em>The equation would be d=90t because the input is 25 for t and multiply to get 2250 feet per second</em>. </h2>
Hey there mate ;)
Note that the quadratic function
A(x) = x(100-2x) gives the area.
Now, this equation is equivalent to:
A(x) = 100x - 2x²
To find maximum value of A, we first find the derivative of the given function:
Now find the critical value by setting dA/dx=0, that is:-
Solving for x, we get:
Hence, the critical point is x=25
Now, Find 2nd derivative to check if the equation has maximum value:
Noting that the 2nd derivative is negative, hence, we have a maximum value. Infact, the maximum value in this case is when the value of x = 25.
The maximum area is therefore,
→ The Correct answer is:
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⣀⣀⣀⣀⣀⣀⣀⣀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠻⡿⠛⠛⠛⠛⠻⢿⡿⠃⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡄⡇⠀⠀ ⠀⠈⡇⠀⠀⠀⠀⠀⠀⠀
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⠀⣀⠀⣠⣤⢀⣀⣠⣤⣤⣤⣤⣤⣿⣿⣿⣄⣼⣿⣿⣿⣿⣿⣿⣿⣦⣀⠀⠀⠀
⢰⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡿⠛⠛⠛⠛⠻⣿⣷⠀⠀
⣸⣿⣿⣿⡿⠛⠛⠛⠻⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡏⠀⠀⠀⠀⠀⠀⠘⣿⡷⠀
⠻⢿⣿⡏⠀⠀⣶⠀⠀⢻⣿⣿⣿⣿⣿⣿⣿⣿⣿⡄⠀⠀⠀⠀⠀⠀⠀⣿⣧⣀
⠀⠀⢹⣷⡀⠀⠀⠀⢀⣿⣿⣉⡉⠉⠉⠉⠉⢙⣿⣷⣄⠀⠀⠀⠀⢀⣼⣿⠛⠓
⠀⠈⠛⠛⠛⠓⠒⠚⠛⠛⠛⠛⠛⠋⠙⠛⠛⠛⠛⠟⠿⠷⠶⠶⠾⠿⢿⠿⠿⠿ Don't mind me, just a feller out on the farm.
Y=x2 the extreme would be x=0
I assume all these measures are normally distributed, in which case the median and mean are equal.
15a. 
because the normal distribution is symmetric about the mean, and so 50% of families have an income greater than the average.
15b. 
by definition of percentile. The 90th percentile is $178,500, so the top 10% of families earn more than this.
15c. Because it's continuous, this distribution has the property 
. The top 10% earn more than $178,500, so the remaining 90% earn less. 50% of families earn more than the average, so 50% of families earn less than the average. Then 
so 40% of families earn between the median and 90th percentile.
16a. 
or 75% because the first quartile is $570, meaning 25% of renters pay less than this amount.
16b. 
or 50% by the same reasoning used in (15a).
16c. 
or 25% by the same reasoning as in (15c).
