Answer: The correct answer is: [D]: "8" .
Step-by-step explanation:f y varies inversely with x; then y = k/x ; with "k" being the "constant" in this equation.
You can find the constant by substituting the values given: x = 16, f(x) = y = 2 ;
So, f(x) = y = 2 = k/16 ;
→ 2 = k / 16 ;
Solve for the constant; "k" ;
Multiply EACH SIDE of the equation by "16"
→ 16* (2) = (k / 16) * 16 ;
→ 32 = k ;
↔ k = 32 ;
As such, we can write the equation:
y = k/ x ; as:
→ y = 32/ x ;
Since we are given: "x = 4" ; Plug in that value; and solve for "y" ;
y = 32/4 = 8 .
y = 8 .
y = f(x) ;
So; f(x) = 8 ; which is: Answer choice: [D]: "8" .
3. (a)
Add the three totals.
Total sales for all three: $2030 + $1540 + $1800 = $5370
Now divide each person's sales by the total sales to find each person's fraction of the sales.
Lola: 2030/5370
Ahmed: 1540/5370
Tommy: 1800/5370
3. (b)
Multiply each fraction from part (a) by $100.
Lola: 2030/5370 * $100 = $37.80
Ahmed: 1540/5370 = $28.67
Tommy: 1800/5370 = $33.52
You're correct, the answer is C.
Given any function of the form
, then the derivative of y with respect to x (
) is written as:
In which
is any constant, this is called the power rule for differentiation.
For this example we have
, first lets get rid of the quotient and write the expression in the form
:
Now we can directly apply the rule stated at the beginning (in which
):
Note that whenever we differentiate a function, we simply "ignore" the constants (we take them out of the derivative).
Answer:
A. E(x) = 1/n×n(n+1)/2
B. E(x²) = 1/n
Step-by-step explanation:
The n candidates for a job have been ranked 1,2,3....n. Let x be the rank of a randomly selected candidate. Therefore, the PMF of X is given as
P(x) = {1/n, x = 1,2...n}
Therefore,
Expectation of X
E(x) = summation {xP(×)}
= summation {X×1/n}
= 1/n summation{x}
= 1/n×n(n+1)/2
= n+1/2
Thus, E(x) = 1/n×n(n+1)/2
Value of E(x²)
E(x²) = summation {x²P(×)}
= summation{x²×1/n}
= 1/n
