What is the value of x

Alabama Instruments Company has set up a production line to manufacture a new calculator. The rate of production of these calcul

kondaur [170]

Answer:

Calculators from the beginning of the third week to the end of the fourth week = 4048.

Step-by-step explanation:

We know that the rate of production of these calculators after t weeks is given by

$\frac{dx}{dt} =5000(1-\frac{100}{(t+10)^{2}})$

To find the number of calculators that have been produced in a period, we need to take the integral of the function above; the desired time is t=2 (beginning of third week) to t=4 (end of the fourth week). Therefore, the number of calculators produced in the given time is

$\int\limits^4_2 {\frac{dx}{dt} } \, dt = \int\limits^4_2 {5000(1-\frac{100}{(t+10)^{2} }) } \, dt$

Substitute $t+10=u$ and $dt=du$ , observe that the limits of integration will change

$\int\limits^4_2 {\frac{dx}{dt} } \, dt => \int\limits^{14}_{12} {\frac{du}{dt} } \, dt$

$5000\int\limits^{14}_{12} { 1-\frac{100}{u^{2} } } \, du$

$5000(u+100u^{-1})\left \{ {{14} \atop {12}}\right.\\5000(2+\frac{100}{14}-\frac{100}{12} )\\4047.62$ ≈ 4048

4 0

3 years ago

Write the quadratic function in the form g(x)=a (x-h)2 +kThen, give the vertex of its graph. G(x) =2x2 +20x+49Writing in the for

Snezhnost [94]

The quadratic function given to us is:

$g(x)=2x^2+20x+49$

We are asked to find the vertex form of the function.

The general formula for the vertex form of a quadratic equation is:

$\begin{gathered} g(x)=a(x-h)^2+k \\ \text{where,} \\ (h,k)\text{ is the coordinate of the vertex} \end{gathered}$

In order to write the function in its vertex form, we need to perform a couple of operations on the function.

1. Add and subtract the square of the half of the coefficient of x to the function.

2. Factor out the function with its repeated roots and re-write the equation.

Now, let us solve.

1. Add and subtract the square of the half of the coefficient of x to the function.

$\begin{gathered} g(x)=2x^2+20x+49=2(x^2+10x+\frac{49}{2}) \\ \text{half of coefficient of x:} \\ \frac{10}{2}=5 \\ \text{square of the half of the coefficient of x:} \\ 5^2=25 \\ \\ \therefore g(x)=2(x^2+10x+25-25+\frac{49}{2}) \end{gathered}$

2. Factor out the function with its repeated roots and re-write the equation.

$\begin{gathered} g(x)=2(x^2+10x+25)-2(25+\frac{49}{2}) \\ re-\text{write the above function} \\ g(x)=2(x^2+10x+25)-1 \\ \text{Let us factorize this:} \\ g(x)=2(x+5)^2-1 \end{gathered}$

Therefore, we can conclude that the Equation and vertex of the equation is:

$\begin{gathered} Equation\colon g(x)=2(x+5)^2-1 \\ \\ Vertex\colon(-5,-1) \end{gathered}$

5 0

2 years ago

Plz, Help me with this question.

UNO [17]

Answer:

first option

Step-by-step explanation:

Given

area = 15x - 9 ← factor out 3 from each term

= 3(5x - 3)

Thus the dimensions are 3 by (5x - 3)

6 0

3 years ago

Read 2 more answers

Which value is equivalent to 9^c x 9^-c A. 0 B. 1 C. 1/9^2C D. 9

AleksAgata [21]

Answer:

B

Step-by-step explanation:

Using the rule of exponents

$a^{m}$ × $a^{n}$ = $a^{(m+n)}$

$a^{0}$ = 1

Given

$9^{c}$ × $9^{-c}$

= $9^{(c-c)}$

= $9^{0}$

= 1 → B

7 0

3 years ago

To qualify for a police academy, candidates must score in the top 10% on a general abilities test. The test has a mean of 200 an

kolbaska11 [484]

Answer:

z = 1.28 < a - 200/20

And if we solve for a we got

a = 200 + 1.28 * 20 = 225.6

So the value of height that separates the bottom 90% of data from the top 10% is 225.6.

Step-by-step explanation:

Let X the random variable that represent the scores of a population, and for this case we know the distribution for X is given by:

X ~ N (200,20)

For u = 200 and o = 20

For this case we can use the z score in order to solve this problem, given by this formula:

Z = x-u/o

For this part we want to find a value a, such that we satisfy this condition:

P (X > a) = 0.1 (a)

P (X < a) = 0.9 (b)

Both conditions are equivalent on this case. We can use the z score again in order to find the value a.

As we can see on the figure attached the z value that satisfy the condition with 0.9 of the area on the left and 0.1 of the area on the right it's z=1.28. On this case P(Z<1.28)=0.9 and P(z>1.28)=0.1

If we use condition (b) from previous we have this:

P ( X < a) = P (X-u/o < a - u/o) = 0.9

P (z < a-u/o) = 0.9

But we know which value of z satisfy the previous equation so then we can do this:

z = 1.28 < a - 200/20

And if we solve for a we got

a = 200 + 1.28 * 20 = 225.6

So the value of height that separates the bottom 90% of data from the top 10% is 225.6.

3 0

3 years ago