Please pleasse help math graph 17 pts

The first eight quizzes in this class had average scores of 8,9,9,8,8,9,8,7. This gives a sample mean of 8.25 and a sample stand

alexira [117]

Answer:

Test statistic

$t = \frac{x^{-} -mean}{\frac{S}{\sqrt{n} } }$

t = 1.076

Step-by-step explanation:

Step(i):-

Given Mean of the Population (μ) = 8.0

Mean of the sample (x⁻) = 8.25

Given data

8,9,9,8,8,9,8,7

Given sample size n= 8

Given sample standard deviation(S) = 0.661

Step(ii):-

Null hypothesis : H: (μ) = 8.0

Alternative Hypothesis :H:(μ) > 8.0

Degrees of freedom = n-1 = 8-1=7

Test statistic

$t = \frac{x^{-} -mean}{\frac{S}{\sqrt{n} } }$

$t = \frac{8.25 -8.0}{\frac{0.661}{\sqrt{8} } }$

t = 1.076

Critical value

t₍₇,₀.₀₅₎ = 2.3646

The calculated value t = 1.076 < 2.3646 at 0.05 level of significance

Null hypothesis is accepted

Test the hypothesis that the true mean quiz score is 8.0 against the alternative that it is not greater than 8.0

3 0

3 years ago

In a carnival game, the player selects a ball one at a time, without replacement, from an urn containing twotwo purplepurple

dezoksy [38]

The urn contains 2 purple balls and 4 white balls. The player pay $4 for start the game and get $1.5 for every ball drawn until one purple ball is drawn. The maximal revenue would be $7.5 when 4 white balls and 1 purple balls are drawn.
If the purple ball is p and white ball is w, the possible sample space of drawings are {p, wp, wwp, wwwp, wwwwp}

1. Write down the probability distribution for the player earning

The player earning for each event depends on the number of balls drawn subtracted the ticket price.
p= 2/6
The player earnings would be: 1*$1.5 -$4= - $2.5
wp= (4*2)/(6*5) = 4/15
The player earnings would be: 2*1.5- $4= - $1
wwp= (4*3*2)/(6*5*4)= 1/5
The player earnings would be: 3*$1.5 -$4= $0.5
wwwp= (4*3*2*2)/(6*5*4*3*2)= 2/15
The player earnings would be: 4*$1.5 -$4= $2
wwwwp= (4*3*2*2*1)/(6*5*4*3*2*1) = 1/15
The player earnings would be: 5*$1.5 -$4= $3.5

2. Find its expected value

The expected value would be:
chance of event * earning
You need to combine the 5 possible outcomes from the number 1 to get the total expected value.

Total expected value= (1/3 * - 2.5)+ (4/15*-1) + (1/5*0.5) + (2/15 *2) + ( 1/15 *3.5)=
(-12.5 -4 + 1.5 + 4 + 3.5) /15= -$7.5
This game basically a rip off.

6 0

3 years ago

Point m is the midpoint of AB. if the coordinates of m (2,8) in the coordinates of A (10, 12) are the coordinates of B

vivado [14]

Point m is the midpoint of AB. if the coordinates of m (2,8) in the coordinates of A (10, 12) are the coordinates of B this is your answer 4/8

8 0

3 years ago

Read 2 more answers

Suppose $600 is compounded yearly for 20 years. If no other deposits are made, what rate is needed for the balance to triple in

denis-greek [22]

Answer:

5.65%

Step-by-step explanation:

Principal=$600

Time=20 years

FV=600*3=$1800

n=1

r=?

r= n[(A/P)^1/nt - 1]

=1{(1800/600)^ 1/1*20 - 1}

={(3)^1/20-1}

=3^0.05-1

=1.0565-1

=0.0565

rate=0.0565*100

=5.65% to the nearest hundredth percent

4 0

3 years ago

BRAINLIESSTTTT ASAP !!!!!!!!!! 20 pointssss

Mars2501 [29]

Answers:
_____________________________________________________
Part A) " (3x + 4) " units .
_____________________________________________________
Part B) "The dimensions of the rectangle are:

" (4x + 5y) " units ; AND: " (4x − 5y)" units."
_____________________________________________________

Explanation for Part A):
_____________________________________________________

Since each side length of a square is the same;

Area = Length * width = L * w ; L = w = s = s ;

in which: " s = side length" ;

So, the Area of a square, "A" = L * w = s * s = s² ;

{Note: A "square" is a rectangle with 4 (four) equal sides.}.

→ Each side length, "s", of a square is equal.

Given: s² = "(9x² + 24x + 16)" square units ;

Find "s" by factoring: "(9x² + 24x + 16)" completely:

→ " 9x² + 24x + 16 ";

Factor by "breaking into groups" :

"(9x² + 24x + 16)" =

 → "(9x² + 12x) (12x + 16)" ;
_______________________________________________________

Given: " (9x² + 24x + 16) " ;
_______________________________________________________
Let us start with the term:
_______________________________________________________

" (9x² + 12x) " ;

 → Factor out a "3x" ; → as follows:
_______________________________________

 → " 3x (3x + 4) " ;

Then, take the term:
_______________________________________
→ " (12x + 16) " ;

And factor out a "4" ; → as follows:
_______________________________________

→ " 4 (3x + 4) "
_______________________________________
We have:

" 9x² + 24x + 16 " ;

= " 3x (3x + 4) + 4(3x + 4) " ;
_______________________________________
Now, notice the term: "(3x + 4)" ;

We can "factor out" this term:

3x (3x + 4) + 4(3x + 4) =

→ " (3x + 4) (3x + 4) " . → which is the fully factored form of:

" 9x² + 24x + 16 " ;
____________________________________________________
→ Or; write: " (3x + 4) (3x + 4)" ; as: " (3x + 4)² " .
____________________________________________________
→ So, "s² = 9x² + 24x + 16 " ;

Rewrite as: " s² = (3x + 4)² " .

→ Solve for the "positive value of "s" ;

→ {since the "side length of a square" cannot be a "negative" value.}.
____________________________________________________
→ Take the "positive square root of EACH SIDE of the equation;
to isolate "s" on one side of the equation; & to solve for "s" ;

→ ⁺√(s²) = ⁺√[(3x + 4)²] '

To get:

→ s = " (3x + 4)" units .
_______________________________________________________

Part A): The answer is: "(3x + 4)" units.
____________________________________________________

Explanation for Part B):
_________________________________________________________

The area, "A" of a rectangle is:

A = L * w ;

in which "A" is the "area" of the rectangle;
"L" is the "length" of the rectangle;
"w" is the "width" of the rectangle;
_______________________________________________________
Given: " A = (16x² − 25y²) square units" ;

→ We are asked to find the dimensions, "L" & "w" ;
→ by factoring the given "area" expression completely:
____________________________________________________
→ Factor: " (16x² − 25y²) square units " completely '

Note that: "16" and: "25" are both "perfect squares" ;

We can rewrite: " (16x² − 25y²) " ; as:

= " (4²x²) − (5²y²) " ; and further rewrite the expression:
________________________________________________________
Note:
________________________________________________________
" (16x²) " ; can be written as: "(4x)² " ;

↔ " (4x)² = "(4²)(x²)" = 16x² "

Note: The following property of exponents:

→ (xy)ⁿ = xⁿ yⁿ ; → As such: " 16x² = (4²x²) = (4x)² " .
_______________________________________________________
Note:
_______________________________________________________

→ " (25x²) " ; can be written as: " (5x)² " ;

↔ "( 5x)² = "(5²)(x²)" = 25x² " ;

Note: The following property of exponents:

→ (xy)ⁿ = xⁿ yⁿ ; → As such: " 25x² = (5²x²) = (5x)² " .
______________________________________________________

→ So, we can rewrite: " (16x² − 25y²) " ;

as: " (4x)² − (5y)² " ;

→ {Note: We substitute: "(4x)² " for "(16x²)" ; & "(5y)² " for "(25y²)" .} . ;
_______________________________________________________
→ We have: " (4x)² − (5y)² " ;

→ Note that we are asked to "factor completely" ;

→ Note that: " x² − y² = (x + y) (x − y) " ;

→ {This property is known as the "difference of squares".}.

→ As such: " (4x)² − (5y)² " = " (4x + 5y) (4x − 5y) " .
_______________________________________________________
Part B): The answer is: "The dimensions of the rectangle are:

" (4x + 5y) " units ; AND: " (4x − 5y)" units."
_______________________________________________________

7 0

3 years ago