A teacher claims that over 5% of statistics students have cheated in his classes in the past few years. In a random sample of 350 statistics students, he has caught 25 students cheating in the past few years. Is there enough evidence to support the teacher’s claim?

Answer:

Following are the solution to the given points:

Step-by-step explanation:

Normal Distribution:

[tex]\mu=50\\\\\sigma= 6\\\\Z=\frac{X-\mu}{\sigma} \sim N(O,l)[/tex]

For point a:

[tex]P(X< 56)=\frac{(56-50)}{6}= \frac{6}{6}=1\\\\[/tex]

[tex]=P(Z<1)\ From\ \sigma \ Table=0.8413\\\\P(X>= 56)=(1-P(X< 56))=1-0.8413=0.1587\\\\[/tex]

For point b:

[tex]P(X< 49)=\frac{(49-50)}{6}=-\frac{1}{6} =-0.1667\\\\=P(Z<-0.1667)\ From\ \sigma \ Table\\\\=0.4338[/tex]

For point c:

To Find [tex]P(a\leq Z\leq b)= F(b) - F(a)\\\\[/tex]

[tex]P(X< 45)=\frac{(45-50)}{6}=\frac{-5}{6} =-0.8333\\\\P (Z<-0.8333) \ From \ \sigma \ Table\\\\=0.20233\\\\P(X< 55)=\frac{(55-50)}{6} =\frac{5}{6}=0.8333\\\\P ( Z< 0.8333) \ From \ \sigma\ Table\\\\=0.79767\\\\P(45 < X < 55) =0.79767-0.20233 =0.5953[/tex]

Answer:

C    

If x = o then f(0) = 4(2) * 0 = 0

If f(x) = 4(2) 0 - 13

then f(x) = -13 at x = 0

Answer:

it will indeed be c

Step-by-step explanation:

deesnuts

Answer:

A and B        because if you count they both have 16 and C has 25

Answer:

concave up:(-3, ∞)

concave down: (-∞, -3)

inflection point: (-3, 0)

Step-by-step explanation:

Concave up is when the slope increases, and concave down is when the slope decreases. Here, we can see that, as we move left to right, when x is less than -3, the slope starts out really high (y is increasing rapidly) but is decreasing. Then, as x reaches -3, the slope starts to rise, and the change in y gets higher and higher.

Given this information, we can say that the function is concave down from (-∞, -3) as it is going down from all values until x=-3 and is concave up from (-3, ∞) as it is going up from all values past x= -3 , with an inflection point of (-3, 0) as that is when the change in slope goes from down to up.

9514 1404 393

Answer:

  0.65 ≤ x ≤ 2.35

Step-by-step explanation:

The ± symbol is pronounced "plus or minus." Then 1.5 ± 0.85 means ...

  1.5 + 0.85 = 2.35   or   1.5 - 0.85 = 0.65

These are said to be the end points of a closed* interval, so the interval is ...

  0.65 ≤ x ≤ 2.35

This is graphed as solid dots at 0.65 and 2.35 and the number line shaded between those dots.

_____

* "closed" means the endpoints are included in the interval. An interval is "open" if the endpoint is not included. The inequality for that is written using the < symbol instead of the ≤ symbol.

9514 1404 393

Answer:

Step-by-step explanation:

Let x and y represent the cost of a hot dog and a hamburger, respectively. The the two purchases can be described by ...

  3x +2y -9.75 = 0

  2x +3y -10.25 = 0

We can list the coefficients of these general-form equations in 2 rows, listing the first one again at the end:

  3, 2, -9.75, 3

  2, 3, -10.25, 2

Now, we can form differences of cross-products in adjacent pairs of columns:

  d1 = (3)(3) -(2)(2) = 9 -4 = 5

  d2 = (2)(-10.25) -(3)(-9.75) = -20.50 +29.25 = 8.75

  d3 = (-9.75)(2) -(-10.25)(3) = -19.50 +30.75 = 11.25

Then the solutions are found from ...

  1/d1 = x/d2 = y/d3

  x = d2/d1 = 8.75/5 = 1.75

  y = d3/d1 = 11.25/5 = 2.25

The cost of one hot dog is $1.75; the cost of one hamburger is $2.25.

_____

Additional comment

This is my simplification of the "cross-multiplication method" of solving a pair of linear equations. That method can be found described on web sites and in videos. This version, and the versions described elsewhere, are variations on Cramer's Rule and on the Vedic Maths method of solving equations. Each of those do similar differences of cross products, perhaps in less-easily-remembered fashion.

For a given pair of columns with coefficients ...

  a b

  c d

The cross-product we form is ad -cb.

Answer:

77 cm²

Step-by-step explanation:

The figure can be decomposed into two rectangles.

✔️Area of rectangle 1:

Area of rectangle 1 = length * width

length = 3.5 cm

width = 8 cm

Area of rectangle 1 = 3.5*8 = 28 cm²

✔️Area of rectangle 2:

Area of rectangle 2 = length * width

length = 14 cm

width = 3.5 cm

Area of rectangle 2 = 14*3.5= 49 cm²

✔️Area of the figure = 28 + 49 = 77 cm²

Answer:

Answer:

Solution given:

f(x)=5x-3

let

y=f(x)

y=5x-3

interchanging role of x and y

x=5y-3

x+3=5y

y=[tex]\frac{x+3}{5}[/tex]

$o,

f-¹(x)=[tex]\frac{x+3}{5}[/tex]

we conclude that

f-¹(x)≠g(x)

Each pair of function are not inverses.

g(x)=x/5+3

let g(x)=y

y=x/5+3

interchanging role of x and y

x=y/5+3

x-3=y/5

doing crisscrossed multiplication

5(x-3)=y

y=5x-15

g-¹(x)=5x-15

So

g-¹(x)≠f-¹(x)

Each pair of function are not inverses.

9514 1404 393

Answer:

Step-by-step explanation:

"Periods" will be filled with the number of years (1) times the number of periods per year (quarterly = 4). periods = 4

"Rate" is likely filled with the rate of interest divided by the number of periods per year. rate = 4%/4 = 1%

Then the total amount is found by ...

  total amount = principal × (1 + rate)^(periods)

  = 575 × (1.01^4) = 598.35

The total interest is the difference between this amount and the principal.

  total interest = total amount - principal

  = 598.35 -575 = 23.35

_____

We believe we have made reasonable assumptions regarding the intent of the columns in the table. Your best bet is to compare this problem to the worked examples in your curriculum materials.

Answer:

277 cm

Step-by-step explanation:

[tex]A=l*w\\3,878=l*14\\l=\frac{3,878}{14} \\l=277[/tex]

Answer:

combination  91 ways

Step-by-step explanation:

This is a combination since order doesn't matter

Permutation are when order matter

14 choose 2 order doesnt matter

14*13

--------

2*1

91 different ways

Step-by-step explanation:

there are two answers for a

Answer:

The ANSWER IS 1/6

Step-by-step explanation:

Answer:

t=55+6w

Hope This Helps!!!

Answer:

10 candy bars

Step-by-step explanation:

Since each of his friends needs a candy bar, you need to multiply 6 and 1 ⅔ together.

First, convert 1 ⅔ into an improper fraction: this gives us ⁵⁄₃.

Next, multiply ⁶⁄₁ and ⁵⁄₃ together. To do this, you can visualize 6 as ⁶⁄₁ (which is the same thing). Now you have ⁶⁄₁ x ⁵⁄₃.

Simplify:

The 6 in the numerator and the 3 in the denominator cancel out. This gives us ²⁄₁ x ⁵⁄₁ , which is 2 x 5.

2 x 5 = 10

9514 1404 393

Answer:

  (a) -- the correct choice is highlighted

Step-by-step explanation:

The units of specific heat tell you what quantities make up the ratio.

  [tex]\dfrac{390\text{ J}}{1\text{ kg$\cdot^\circ$C}}=\dfrac{-12.0\text{ J}}{0.012\text{ kg}\cdot\Delta T}\\\\\Delta T=\dfrac{-12.0}{0.012\cdot390}\ ^\circ\text{C}\approx-2.56\text{ $^\circ$C}[/tex]

The temperature will decrease by 2.56 C.

Answer:

[tex]{ \tt{ \frac{y}{x} = - \frac{6}{7} }} \\ { \tt{y = - \frac{6}{7}x }} \\ { \boxed{ \bf{constant = - \frac{6}{7} }}}[/tex]

Answer:

Seth would need 10 hours to paint the room.

Step-by-step explanation:

Let's define:

S = rate at which Seth works

T = rate at which Ted works

When they work together, the rate is S + T

And we know that when they work together they can pint one room in 5 hours, then we can write:

(S + T)*5 h = 1 room.

We also know that Ted alone would need one hour more than Seth alone.

Then if Seth can paint the room in a time t, we have:

S*t = 1room

and

T¨*(t + 1h) = 1room

Then we have 3 equations:

(S + T)*5 h = 1

S*t = 1

T¨*(t + 1h) = 1

(I removed the "room" part so it is easier to read)

We want to find the value of S.

First, let's isolate one variable (not S) in one of the equations.

We can isolate t in the second one, to get:

t = 1/S

Now we can replace it on the third equation:

T¨*(t + 1h) = 1

T¨*( 1/S + 1h) = 1

Now we need to isolate T in this equation, we will get:

T = 1/( 1/S + 1h)

Now we can replace this in the first equation:

(S + T)*5h = 1

(S + 1/( 1/S + 1h) )*5h = 1

Now we can solve this for S

(S + 1/( 1/S + 1h) )= 1/5h

S + 1/(1/S + 1h) = 1/5h

Now we can multiply both sides by (1/S + 1h)

(1/S + 1h)*S + 1 = (1/5h)*(1/S + 1h)

1 + S*1h + 1 = 1/(S*5h) + 1/5

S*1h + 2 = (1/5h*S) + (1/5)

Now we can multiply both sides by S, to get:

(1h)*S^2 + 2*S = (1/5h) + (1/5)*S

Now we have a quadratic equation:

(1h)*S^2 + 2*S  - (1/5)*S -  (1/5h) = 0

(1h)*S^2 + (9/5)*S - (1/5h) = 0

The solutions are given by the Bhaskara's formula:

[tex]S = \frac{-(9/5) \pm \sqrt{(9/5)^2 - 4*(1h)*(-1/5h)} }{2*1h} = \frac{-9/5 \pm 2}{2h}[/tex]

Then the solution (we only take te positive one) is:

S = (-9/5 + 2)/2h

S = (-9/5 + 10/5)/2h = (1/5)/2h = 1/10h

Then Seth needs a time t to paint one room:

(1/10h)*t = 1

t = 1/(1/10h) = 10h

So Seth would need 10 hours to paint the room.

Answer:

192

Step-by-step explanation:

Multiply all numbers together.

2 * 4 * 3 * 8 = 192

Answer:

it's 192 because you have to multiply all of the numbers to get 192

Answer:

24

Step-by-step explanation:

6 x 4 = 24

Answer:

Step-by-step explanation:

4⁶=4096

Total number of ways to select 3 people from the 5 total: 5!/(3! (5 - 3)!) = 10

• Number of ways of picking 0 women:

[tex]\dbinom20\times\dbinom33 = 1\times1 = 1[/tex]

• Number of ways of picking 1 woman:

[tex]\dbinom21\times\dbinom32 = 2\times3 = 6[/tex]

• Number of ways of picking 2 women:

[tex]\dbinom22\times\dbinom31 = 1\times3 = 3[/tex]

• Number of ways of picking 3 women: 0, since there are only 2 to choose from

Then X has the probability mass function

[tex]P(X=x) = \begin{cases}\frac1{10}&\text{if x=0}\\\frac6{10}=\frac35&\text{if }x=1\\\frac3{10}&\text{if }x=2\\0&\text{otherwise}\end{cases}[/tex]

Answer:

x = -2: y = 8.5

x = -1: y = 4

x = 0: y = -0.5

x = 1: y = -5

x = 2: y = -9.5

Step-by-step explanation:

We find the numeric values for the function from x = -2 to x = 2.

x = -2:

[tex]y = -4.5(-2) - 0.5 = 9 - 0.5 = 8.5[/tex]

x = -1:

[tex]y = -4.5(-1) - 0.5 = 4.5 - 0.5 = 4[/tex]

x = 0:

[tex]y = -4.5(0) - 0.5 = 0 - 0.5 = -0.5[/tex]

x = 1:

[tex]y = -4.5(1) - 0.5 = -4.5 - 0.5 = -5[/tex]

x = 2:

[tex]y = -4.5(2) - 0.5 = -9 - 0.5 = -9.5[/tex]

Answer:

175.

Step-by-step explanation:

40 = 2*2*2*5

1400 = 2*2*2*5*5*5*7

So by inspection we have x = 5*5*7 = 175

Answer:

[tex]x=0,x=-2[/tex]

Step-by-step explanation:

From the question we are told that:

[tex]y=2x^5+5x^4-19[/tex]

Generally the equation if differentiated is mathematically given by

[tex]y'=10x^4+20x^3-0[/tex]

Where

y'=0

[tex]10x^4+20x^3=0[/tex]

Factorizing,We have

[tex]x=0,x=-2[/tex]

Therefore

The critical points are

[tex]x=0,x=-2[/tex]

Excellent question, but let's rephrase it.

Suppose you have a square of surface area of 2851.

What would be a hundredth of such square?

What would be surface area of that hundredth.

Why hundredth? Because percent denotes hundredths cent is a latin word for hundred. You would usually encounter similar word that describes 100 years: century.

Well it is actually very easy. Just divide 2851 into 100 pieces and look at what is the area of one piece.

[tex]2851/100=285.1=y[/tex]

So a single piece has an area of 258.1.

Hope this helps. :)

[tex]1\pm\sqrt{2}i[/tex]

Step-by-step explanation:

We already know that one of the roots is x = -4 so we can factor this out to get

[tex]x^3+2x^2-5x+12=(x+4)(x^2-2x+3)[/tex]

Using the quadratic equation on the 2nd factor, we find the roots are

[tex]x= \dfrac{2\pm\sqrt{(2)^2 - 4(1)(3)}}{2}=1\pm\sqrt{2}i[/tex]

Option A

Answered by GauthMath if you like please click thanks and comment thanks

9514 1404 393

Answer:

  57

Step-by-step explanation:

Apparently, you want to simplify ...

  [tex]\displaystyle \frac{1}{\sqrt{2} + \sqrt{3} + \sqrt{7}}[/tex]

so the denominator is rational. It looks like the form you want is ...

  [tex]\dfrac{A\sqrt{2} + B\sqrt{3} + C\sqrt{7} + D\sqrt{E}}{F}[/tex]

And you want to know the sum A+B+C+D+E+F.

__

We can start by multiplying numerator and denominator by a conjugate of the denominator. Then we can multiply numerator and denominator by a conjugate of the resulting denominator.

  [tex]\displaystyle =\frac{1}{\sqrt{2} + \sqrt{3} + \sqrt{7}}\cdot\frac{\sqrt{2} + \sqrt{3} - \sqrt{7}}{\sqrt{2} + \sqrt{3} - \sqrt{7}}=\frac{\sqrt{2} + \sqrt{3} - \sqrt{7}}{2\sqrt{6}-2}\\\\=\frac{\sqrt{2} + \sqrt{3} - \sqrt{7}}{2\sqrt{6}-2}\cdot\frac{\sqrt{6}+1}{\sqrt{6}+1}=\frac{(1+\sqrt{6})(\sqrt{2}+\sqrt{3}-\sqrt{7})}{10}\\\\=\frac{\sqrt{2}+\sqrt{3}-\sqrt{7}+2\sqrt{3}+3\sqrt{2}-\sqrt{42}}{10}=\frac{4\sqrt{2}+3\sqrt{3}-\sqrt{7}-\sqrt{42}}{10}[/tex]

Comparing this to the desired form we have ...

  A = 4, B = 3, C = -1, D = -1, E = 42, F = 10

Then the sum is ...

  A +B +C +D +E +F = 4 + 3 -1 -1 +42 +10 = 59 -2 = 57

The sum of interest is 57.