A student decides she wants to save money to buy a used car, which costs $2600. She comes up with what she thinks is a very modest savings plan. She decides to save 2 cents the first day and double the amount she saves each day thereafter. On the second day she plans to save 4 cents, on the third day, 8 cents, and so on. Determine how long it will take her to save enough money to buy the car ?

Answer:

X = 101.48

Step-by-step explanation:

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Average of 62 seconds with a standard deviation of 24.5 seconds.

This means that [tex]\mu = 62, \sigma = 24.5[/tex]

If the manager wants to advertize that 95% of the time, they serve customers within X seconds, what is the value of X?

This is the 95th percentile of times, which is X when Z has a p-value of 0.95, so X when Z = 1.645.

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]1.645 = \frac{X - 62}{24.5}[/tex]

[tex]X - 62 = 1.645*24[/tex]

[tex]X = 101.48[/tex]

Answer:

Step-by-step explanation:

The probability that a person answered incorrectly is 4/5

P(1st answered incorrectly AND 2nd answered incorrectly AND

3rd answered incorrectly AND 4th answered incorrectly AND

5th answered incorrectly AND 6th answered incorrectly AND

7th answered incorrectly AND 8th answered incorrectly)

Since "AND" mean to multiply, the probability that none of the 8 guessed correctly is

4/5×4/5×4/5×4/5×4/5×4/5×4/5×4/5

=(4/5)^8

=0.16777216

Answer:

didn't get the question did u forget to put the sequence ???????

pls write the question fully so that I can help you

9514 1404 393

Explanation:

There are several ways you can go at this. Here are a couple. All proofs will start with the given relations being repeated as part of the proof. Here are the next steps.

∠AED ≅ ∠BAE . . . . alternate interior angles are congruent

∠AED +∠AEB = 90° . . . . angle sum theorem

∠BAE +∠AEB = 90° . . . . substitution property of equality

∠CEF ≅ ∠BCE . . . . alternate interior angles are congruent

∠CEF +∠CEB = 90° . . . . angle sum theorem

∠BCE +∠CEB = 90° . . . . substitution property of equality

∠BAE +∠AEB = ∠BCE +∠CEB . . . . substitution property of equality

∠BAE +∠AEB = ∠BCE +∠AEB . . . . substitution property of equality

∠BAE = ∠BCE . . . . addition property of equality

∠ABE = ∠CBE = 90° . . . . BE ⊥ AC

BE ≅ BE . . . . reflexive property of congruence

ΔBEA ≅ ΔBEC . . . . ASA congruence theorem

∠BAE ≅ ∠BCE . . . . CPCTC

Answer:

See answers below

Step-by-step explanation:

Given the following functions:

r(x) = x - 6

s(x) = 2x²

r(s(x)) = r(2x²)

Replacing x with 2x² in r(x) will give;

r(2x²) = 2x² - 6

r(s(x)) = 2x² - 6

(r-s)(x) = r(x) - s(x)

(r-s)(x) = x - 6 - 2x²

Rearrange

(r-s)(x) = - 2x²+x-6

(r+s)(x) = r(x) + s(x)

(r-s)(x) = x - 6 + 2x²

Rearrange

(r-s)(x) = 2x²+x-6

Answer:

0.9113

Step-by-step explanation:

Given :

Sample standard deviation of Stock X = 4.665

Sample standard deviation of Stock Y = 8.427

Sample Covariance = 35.826

The Correlation Coefficient, R is related to sample covariance and standard deviation using the formular :

R = Covariance(X, Y) / (SD(X) * (SD(Y))

R = 35.826 / (4.665 * 8.427)

R = 35.826 / 39.311955

R = 0.9113

Hence, correlation Coefficient, R = 0.9113 which depicts a strong positive relationship.

9514 1404 393

Answer:

  B. a = plus-or-minus 4

Step-by-step explanation:

  3a² -21 = 27 . . . . . . . given

  3a² = 48 . . . . . . . . . . add 21 to both sides (desired form)

  a² = 16 . . . . . . . . . . .  divide both sides by 3

  a = ±4 . . . . . . . take the square root

Answer:

0.6

Step-by-step explanation:

In this question, the | symbol means "given", so we can phrase the question as "Find the probability that a student watches more than one hour of TV given that they are in the 6th period class"

Next, because there is a 100% chance that the student is in the 6th period class, we can disregard the results of the 3rd period class.

Given that the student is in the 6th period class, there are 15 total students (as 9+6=15 = the sum of the yes and no answers for 6th period) and 9 students that said yes. Therefore, there is a 9/15 = 3/5 = 0.6 probability that a student watches more than 1 hour of TV given that they are in the 6th period class

Answer:

I think the answer is 5/6

Step-by-step explanation:

There are three even numbers and two uneven numbers less than four. Therefore, on a standard die, the.probability of Rollin a number that is even or less than for is 5/6.

Answer:

1;What are two ways limits may appear graphically? What are the differences between these two limits?

two ways limits may appear graphically are:

,we analyze the graph of the function to determine the points that each of the one-sided limits approach.

A graphical approach is used to find an approximate solution to a problem by viewing an interpreting a graphical image accordingly but

A numerical approach is used to find an approximate solution to a problem but may be simpler than an analytical approach.

Step-by-step explanation:

2. What occurs when the limits of a functions of a function at x is not the same from left to right and from right to left?

Answer:

u = 2

Step-by-step explanation:

Since this is a right triangle, we can use trig functions

cos theta = adj side / hypotenuse

cos 45 = sqrt(2) / u

u cos 45 = sqrt(2)

u = sqrt(2) / cos 45

u = sqrt(2) / 1/ sqrt(2)

u = sqrt(2) * sqrt(2)

u =2

u=2

Answer:

Solution given:

Cos 45°=base/hypotenuse

[tex]\frac{1}{\sqrt{2}}=\frac{\sqrt{2}}{u}[/tex]

doing crisscrossed multiplication

[tex]\sqrt{2}*\sqrt{2}=1*u[/tex]

u=2

Answer:

The total number of ways is 252.

Step-by-step explanation:

Number of girls = 18

number of boys = 14

Commitee of one girl and a boy

(18 C 1)(14 C 1)

= 252

Answer:

[tex]7x {}^{2} + 5x[/tex]

Step-by-step explanation:

[tex]9x {}^{2} + 8x - (2x {}^{2} + 3x) \\ \\ = 9x {}^{2} + 8x - 2x {}^{2} - 3x (remove \: brackets) \\\ \\ = 7x {}^{2} - 5x [/tex]

Answer:

(3x+2) by (2x+1)

Step-by-step explanation:

A cardboard is a rectangle, and has two dimensions. Given a quadratic equation, you should find a way to split it in two.

The easiest way to do so is through factoring. (There are many ways to do this, take a look at the plethora of sources offered on the internet.)

When the expression 6x^2 + 7x + 2 is factored, it is (3x+2)(2x+1). Hence, these are your dimensions.

Answer:

False

Step-by-step explanation:

The absolute value shows the distance a value is from 0, which is always positive.

9514 1404 393

Answer:

  30°

Step-by-step explanation:

The sum of angles in a quadrilateral is 360°.

  230° +C +50° +50° = 360°

  C = 360° -330° = 30°

  m∠C = 30 degrees

Answer:

Step-by-step explanation :

Let % increase in administrative secretary be = x

Let % increase in new faculty receive be = y

Administrative secretary salary = 28,000

New faculty receive Salary = 40,000

(8)*(x/100)* (28000) + (7)*(y/100)*(40000) = 5,000

2240x +2800 y = 5,000

224x +280 y = 500

56x +70y = 125

Therefore, x and y should be chosen such that it satisfy the above equation.

Answer:

0.000000073

Step-by-step explanation:

Given number is,

7.3E - 8

In scientific notation number will be,

7.3 × 10⁻⁸

In standard form the number will be,

0.000000073

Answer:

Kindly check explanation

Step-by-step explanation:

Given the data :

Technician __Shutdown

Taylor, T___4

Rousche, R _ 3

Hurley, H__ 3

Huang, Hu___2

Gupta, ___ 5

The Numbe of samples of 2 possible from the 5 technicians :

We use combination :

nCr = n! ÷ (n-r)!r!

5C2 = 5!(3!)2!

5C2 = (5*4)/2 = 10

POSSIBLE COMBINATIONS :

TR, TH, THu, TG, RH, RHu, RG , HHu, HG, HuG

Sample means :

TR = (4+3)/2 = 3.5

TH = (4+3)/2 = 3.5

THu = (4+2) = 6/2 = 3

TG = (4 + 5) = 9/2 = 4.5

RH = (3+3) = 6/2 = 3

RHu = (3+2) /2 = 2.5

RG = (3 + 5) = 8/2 = 4

HHu = (3+2) = 2.5

HG = (3+5) = 8/2 = 4

HuG = (2+5) / 2 = 3.5

Mean of sample mean (3.5+3.5+3+4.5+3+2.5+4+2.5+4+3.5) / 10 = 3.4

Population mean :

(4 + 3 + 3 + 2 + 5) / 5 = 17 /5 = 3.4

Population Mean and mean of sample means are the same.

This distribution should be approximately normal.

The question is incomplete. The complete question is :

In a​ poll, 1100 adults in a region were asked about their online vs.​ in-store clothes shopping. One finding was that 43​% of respondents never​ clothes-shop online. Find and interpret a ​95% confidence interval for the proportion of all adults in the region who never​ clothes-shop online.

Solution :

95% confidence interval for p is :

[tex]$\hat p - Z_{\alpha/2}\times \sqrt{\frac{\hat p(1-\hat p)}{n}} < p < \hat p + Z_{\alpha/2}\times \sqrt{\frac{\hat p(1-\hat p)}{n}}$[/tex]

[tex]$0.43 - 1.96\times \sqrt{\frac{0.43(1-0.43)}{1100}} < p < 0.43 + 1.96\times \sqrt{\frac{0.43(1-0.43)}{1100}}$[/tex]

0.401 < p < 0.459

Therefore, 95% confidence interval is from 0.401 to 0.459

There are several ways to solve a quadratic equation. I'll complete the square:

z ² - (3 - 2i ) z + 5 - 5i = 0

(z - (3 - 2i )/2)² - ((3 - 2i )/2)² + 5 - 5i = 0

(z - (3 - 2i )/2)² - (3 - 2i )²/4 + 5 - 5i = 0

(z - (3 - 2i )/2)² = (3 - 2i )²/4 - 5 + 5i

(z - (3 - 2i )/2)² = (3² - 2×3×(-2i ) + (-2i )²)/4 - 5 + 5i

(z - (3 - 2i )/2)² = (5 - 12i )/4 - 5 + 5i

(z - (3 - 2i )/2)² = (5 - 12i - 20 + 20i )/4

(z - (3 - 2i )/2)² = (-15 + 8i )/4

Let w = (-15 + 8i )/4. Then write w = |w| exp(i arg(w)), where

|w| = √((-15/4)² + 2²) = 17/4

arg(w) = π - arctan(8/15)

The square roots of w are then

√w = √(|w|) exp(i (arg(w) + 2nπ)/2)

where n in the set {0, 1}.

Taking the square root of both sides gives

z - (3 - 2i )/2 = √w

z = (3 - 2i )/2 + √w

and the two solutions can be simplified to

z = √17/4 + √17 i

z = -√17/4 - √17 i

Answer:

See explanation.

General Formulas and Concepts:

Algebra I

Algebra II

Pre-Calculus

Calculus

Differentiation

Derivative Property [Multiplied Constant]:                                                           [tex]\displaystyle \frac{d}{dx} [cf(x)] = c \cdot f'(x)[/tex]

Derivative Property [Addition/Subtraction]:                                                         [tex]\displaystyle \frac{d}{dx}[f(x) + g(x)] = \frac{d}{dx}[f(x)] + \frac{d}{dx}[g(x)][/tex]

Basic Power Rule:

Derivative Rule [Quotient Rule]:                                                                           [tex]\displaystyle \frac{d}{dx} [\frac{f(x)}{g(x)} ]=\frac{g(x)f'(x)-g'(x)f(x)}{g^2(x)}[/tex]

Parametric Differentiation:                                                                                     [tex]\displaystyle \frac{dy}{dx} = \frac{\frac{dy}{dt}}{\frac{dx}{dt}}[/tex]

Step-by-step explanation:

Step 1: Define

Identify

[tex]\displaystyle x = 2t - \frac{1}{t}[/tex]

[tex]\displaystyle y = t + \frac{4}{t}[/tex]

Step 2: Find Derivative

Here we see that if we increase our values for t, our derivative would get closer and closer to 0.5 but never actually reaching it. Another way to approach it is to take the limit of the derivative as t approaches to infinity. Hence  [tex]\displaystyle \frac{dy}{dx} < \frac{1}{2}[/tex].

Topic: AP Calculus BC (Calculus I + II)

Unit: Parametrics

Book: College Calculus 10e

Let f(x) = ax³ + 9x² + 4x – 10

g(x) = 0⇒x - 3 = 0

⇒ x = 0 + 3

⇒ x = 3

On dividing f(x) by x - 3, it leaves a remainder 5.

Now keeping, f(3) = 5

⇒a(3)³ + 9(3)² + 4(3) - 10 = 5

⇒ a × 27 + 9 × 9 + 4 × 3 - 10 = 5

⇒ 27a + 81 + 12 - 10 = 5

⇒ 81 + 12 - 10 - 5 = 27a

⇒ 81 + 12 - 15 = 27a

⇒ 93 - 15 = 27a

⇒ 78 = 27a

⇒ a = 27/78

⇒ a = 0.3461

Answer:

Step-by-step explanation:

This is nice and simple. I'm going to walk through it like I do when teaching this concept to my class for the first time. This is a good problem for that.

We are given a square and we are looking for the rate at which the area is increasing when a certain set of specifics are given. That means that the main equation for this problem is the area of a square, which is:

[tex]A=s^2[/tex] where s is a side.

Since we are looking for the rate at which the area is changing, [tex]\frac{dA}{dt}[/tex], we need to take the derivative of area formula implicitly:

[tex]\frac{dA}{dt}=2s\frac{ds}{dt}[/tex] that means that if [tex]\frac{dA}{dt}[/tex] is our unknown, we need values for everything else. We are given that the initial area for the square is 49. That will help us determine what the "s" in our derivative is. We plug in 49 for A and solve:

[tex]49=s^2[/tex] so

s = 7

We are also given at the start that the sides of this square are increasing at a rate of 8cm/s. That is [tex]\frac{ds}{dt}[/tex]. Filling it all in:

[tex]\frac{dA}{dt}=2(7)(8)[/tex] and

[tex]\frac{dA}{dt}=112\frac{cm^2}{s}[/tex]

The surface area of a square of side L is given by

[tex]A = L^2[/tex]

The rate of change of the area per unit time is

[tex]\dfrac{dA}{dt} = 2L\dfrac{dL}{dt}[/tex]

We can express the length L on the right hand side in terms of the area A [tex](L = \sqrt{A})[/tex]:

[tex]\dfrac{dA}{dt} = 2\sqrt{A}\dfrac{dL}{dt}[/tex]

[tex]\:\:\:\:\:\:\:=2(\sqrt{49\:\text{cm}^2})(8\:\text{cm/s})[/tex]

[tex]\:\:\:\:\:\:\:=112\:\text{cm}^2\text{/s}[/tex]