please help can’t figure out

The probability that the mean score of the 49 seniors is greater than 20 is 0.0516. To solve this problem, we need to use the central limit theorem, which states that the distribution of sample means from a population with any distribution will approach a normal distribution as the sample size increases.

First, we need to find the standard error of the mean (SEM), which is the standard deviation of the sampling distribution of the mean. We can use the formula SEM = σ / √n, where σ is the population standard deviation, and n is the sample size.

In this case, σ = 6.0 and n = 49, so SEM = 6.0 / √49 = 0.857.

Next, we need to standardize the sample mean using the z-score formula: z = (x - μ) / SEM, where x is the sample mean, μ is the population mean, and SEM is the standard error of the mean.

In this case, x = 20, μ = 18.6, and SEM = 0.857, so z = (20 - 18.6) / 0.857 = 1.63.

Finally, we need to find the probability that a standard normal distribution is greater than 1.63, which is 0.0516 when rounded to 4 decimal places.

Therefore, the probability that the mean score of the 49 seniors is greater than 20 is 0.0516.

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The given algebraic expression is equivalent to the polynomial \(-\frac{10}{7} a^3y^7+\frac{2}{14}a^4y^6+\frac{10}{42} a^5y^5\).

The main power rules are presented below.

For solving this question you should apply the distributive property of multiplication and the power rules.

The question gives:  \(-\frac{2}{7} a^2y^5(5ay^2-\frac{1}{2}a^2y-\frac{5}{6} a^3)\). Applying the power rules - multiplication with the same base, you find:

\(-\frac{10}{7} a^3y^7+\frac{2}{14}a^4y^6+\frac{10}{42} a^5y^5\)

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The system of equations is consistent and has a unique solution at (-4, 1).

To solve the system of equations by graphing, we can plot the lines represented by each equation on a coordinate plane and find their point of intersection.

The given system of equations is:

1) 3x + y = -3

2) 6x - 6y = -30

Let's graph these equations:

For equation 1, 3x + y = -3, we can rewrite it as y = -3x - 3.

For equation 2, 6x - 6y = -30, we can simplify it to x - y = -5, and then y = x + 5.

Now, let's plot these lines on a graph:

The line for equation 1, y = -3x - 3, has a slope of -3 and y-intercept of -3. It will have a negative slope, and we can plot two points on the line: (0, -3) and (-1, 0).

The line for equation 2, y = x + 5, has a slope of 1 and y-intercept of 5. We can plot two points on this line as well: (0, 5) and (-5, 0).

Plotting these lines on a graph, we can see that they intersect at the point (-4, 1).

Now, let's analyze the system:

Since the lines intersect at a single point, the system is consistent. The solution to the system is the coordinates of the point of intersection, which is (-4, 1).

In summary, the system of equations is consistent and has a unique solution of x = -4 and y = 1.

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Answer:

(a+b)/c

Step-by-step explanation:

a/c+b/c

since they have the same denominator you can add the numerator together

(a+b)/c

Answer:

Step-by-step explanation:

Let the 2 point questions = x

Let the 4 point questions = y

This first equation gives the total number of questions.

x + y = 40                 Multiply this question by 2

2x + 2y = 80

The second equation gives the point distribution. The value  of multiple choice answers = 2x. The value of the short answer questions = 4y.

Now write the first equation under this question.

2x + 4y = 100

2x + 2y = 80             Subtract.

2y = 20                     Divide by 2

2y/2 = 20/2            

y = 10

x + y = 40

x + 10 = 40

Subtract 10 from both sides

x = 30

Answer

Answer:\(x<−95+3y5\)

Step-by-step explanation:

Isolate the variable by dividing each side by factors that don't contain the variable.

Answer:

yes htjjevdhfifnfjjdeirjfjebdv dbdu you fr

The scale factor from the map to the actual hiking trails can be found to be 50, 000.

To find the scale factor, we first need to look at the scale which is :

3 cm : 1. 5 km

This scale needs to have the same units of measurement so we can convert the  1.5 km to centimeters.

This becomes :

= 1. 5 x 100, 000 cm per km

= 150, 000 cm

The scale factor for the map to the actual hiking trails is :

= 150, 000  / 3

= 50, 000

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Answer:

Step-by-step Here is the answer I just did it and answer is 90 degrees

Pls mark me brainlyis would like if yo do that :)

I got it wrong just for enjoy

if square ABCD were Rotated 90 clockwise about the origin to create square A’B’C’D. The measure of angle B  is: D. 90.

Given

ABCD=90 Clockwise

Hence:

Rotation will not change the size and figure

Square ABCD≅ Square  A’B’C’D

m∠B=90°

So,

m∠B'=m∠B=90°

Therefore the correct option is D.

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Answer:

tanP = \(\frac{20}{21}\) , tanQ = \(\frac{21}{20}\)

Step-by-step explanation:

tanP = \(\frac{opposite}{adjacent}\) = \(\frac{QR}{PR}\) = \(\frac{20}{21}\)

tanQ = \(\frac{opposite}{adjacent}\) = \(\frac{PR}{QR}\) = \(\frac{21}{20}\)

The number of nickels and dimes that Ariana has are 58 and 91

Linear Equation:

The polynomial equation with 1 degree representing an unknown quantity is known as a Linear equation. Here to represent the unknown quantity we will use variables like x, y, z .... etc.

From the given problem,

The amount that Ariana = $12.00

As we know 1 dollar = 100 cents

⇒ $12.00 = 12 × 100 = 1200 cents  

Total number of nickels and dimes = 149

Since we don't know the number of nickels and dimes we will represent them with variables x and y respectively.

The amount of x nickels coins

= x × 5 cents = 5x cents   [ ∵ nickels = 5 cents ]  

The amount of y dimes coins

= y × 10 cents = 10y cents   [ ∵ dimes = 10 cents ]  

From the above calculations the equation that can be formed

Total amount that Ariana is 5x + 10y = 1200 cents

=> x + 2y = 240 ----- Equation (1)  

Total number of coins is  x + y = 149 ----- Equation (2)    

Now solve (1) and (2) to find the number of each coin  

Do (1) - (2)

=> x + 2y - [ x + y ] = 240 - 149

=> x + 2y - x - y  = 91  

=> y  = 91      

Substitute y = 91 in Equation (2)      

(2) => x + 91 = 149

=> x = 58

The number of nickels and dimes that Ariana has are 58 and 91

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The answer is option d. -1.865, as it is the value that satisfies P(Z ≤ b) = 0.0311. The other options (-1.87, -1.86, -1.8) do not correspond to the given cumulative probability.

In this scenario, P(Z ≤ b) represents the cumulative probability of a standard normal distribution up to the value of b. To find the corresponding value of b, we need to find the z-score that corresponds to a cumulative probability of 0.0311.

By looking up the z-table or using a statistical calculator, we can find that the z-score corresponding to a cumulative probability of 0.0311 is approximately -1.865.

Therefore, the answer is option d. -1.865, as it is the value that satisfies P(Z ≤ b) = 0.0311. The other options (-1.87, -1.86, -1.8) do not correspond to the given cumulative probability.

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Given:

44, 38, 21, 37, 48, 43, 28

To find the box-and-Visker plot representing the given data:

Let us write it in ascending order.

21, 28, 37, 38, 43, 44, 48.

The median of the given data is 38.

The median of the first three terms is 28.

The median of the last three terms is 44.

The lowest of the given data is 21.

The highest of the given data is 48.

Hence, the correct option c.

Answer:

x greater than 126

Step-by-step explanation:

3(x/2)greter than 21

multiply

126

Answer:

Step-by-step explanation:

three times (3 times something) the difference of x and 2 (2-x) is  greater than (>) -21 (-21)

3 times (2-x)>-21

3(2-x)>-21

distrobite using distributiver poerpoty

a(b+c)=ab+ac

3(2-x)=6+(-3x)=6-3x

6-3x>-21

add 3x to both sides

6>-21+3x

add 21 to both sides

27>3x

divide both sides by 3

9>x

x<9

so x= any number below 9 not including 9

To plot the graph of the function:

According to your graphing software, we need to find the smallest value of the function, and any point at the positive slope side of the function. Let's start with the minimum point. Let's use the general formula for an absolute value function:

The coefficients 'b' and 'c' determinates how much the function was translated from the origin. The 'b' determinates in the x-axis, and the 'c' determinates in the y-axis.

If the 'b' is positive, the function translated to the left, if it is negative the function translated to the right.

If the 'c' is positive the function went up, and if it is negative it went down.

Now let's analyze our h(x) function. Our coefficients are:

Which means our minimum point is

Now, we just need to calculate any point to the right of x = -1.

Let's calculate for x = 0.

The second point is (0,7)

Answer:

tan²x + tan x - 12 = 0 (1)

suppose: tan x = t

(1)=> t² + t - 12 = 0

a = 1    b = 1     c = -12

⇒ Δ = b² - 4ac = 1 + 48 = 49 > 0 => has 2 solutions

=> t = \(\frac{1+\sqrt{49} }{2}=\frac{8}{2}=4\)

or t = \(\frac{1-\sqrt{49} }{2}=\frac{-6}{2}= -3\)

because t = tan x => tan x = 4 or tan x = -3

because x ∈ [0;2pi) => with tan x = 4 => x = arctan(4)  or x = arctan(4) + pi

                                     with tan x = -3 => x = arctan(-3) + pi

Step-by-step explanation:

Answer:

B.

Step-by-step explanation:

Answer:

the answer: 280ci

Step-by-step explanation:

:] [:

Answer:

280

Step-by-step explanation:

So the value of discriminant for √ 2x² − 5x + √ 2 = 0 is b. 17

The discriminant of a quadratic equation is the value of the expression under the square root in the quadratic formula. The quadratic formula is used to find the solutions of the equation of the form ax² + bx + c = 0, where a, b and c are constants. The solutions of the equation are given by x = (-b ± √(b² - 4ac))/ 2a. The value under the square root (b² - 4ac) is called the discriminant.

Given equation is √ 2x² − 5x + √ 2 = 0

The discriminant of the equation is the value of b² - 4ac, which is

b² - 4ac = (-5)² - 4 * (√2) * (√2) = 25 - 8 = 17

So the value of discriminant for √ 2x² − 5x + √ 2 = 0 is b. 17

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Answer:

B

Step-by-step explanation:

Answer:

4.2 miles per/hour

Step-by-step explanation:

we know

speed  total distance covered/ total time taken to cover that distance.

Time from 9:00 Am to 11:30 Am is 2 hours 30 minutes

time = 2 1/2 hours = 5/2 hours

for distance\

By 11:30 AM, he was 13 miles from the start.

so he covered a total distance of 12 miles

At 9:00 AM, a person running a race was 2 1/2 miles from the start

until 9 am he had already ran 2 1/2 miles = 5/2 miles

since we have to take distance travelled from 9 to 11 :30 Am

we need to subtract distance travel until 9 am from total distance traveled until 11:30 pm

Distance travlled from 9:11:30 am = distance traveled from start till 11:30AM -  distance traveled from start till 9 AM

Distance traveled from 9:11:30 am =  13 - 5/2 = (26-5)/2 = 21/2

Thus, speed = 21/2 / 5/2 = 21/5 = 4 1/5 miles/hour = 4.2 miles/hour

Thus, he was running with 4.2 miles per/hour.

Answer:

Each one of the little squares is called a unit. they count in a line how many units are on the base. they did the same upward for the height

Step-by-step explanation:

So, Lana gave away 26.32% of he Pokemon cards  to her little brother.

To find the percentage of cards Lana gave away, we can use the formula:(Quantity given away / Total quantity) * 100.

In this case, Lana gave away 125 cards out of her total collection of 475 cards.Plugging these values into the formula, we have:

(125 / 475) * 100 = 0.2632 * 100 = 26.32%.

Lana gave away 26.32% of her Pokemon cards to her little brother.

Alternatively, we can calculate the percentage by subtracting the remaining cards from the total and finding the ratio:

Percentage given away

= (Cards given away / Total cards) * 100

= (125 / 475) * 100

= 26.32%.

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Answer

43days

Step-by-step explanation:

Given that the total number of pages is 300

and Jared has read 85 pages

this means he has 300-85=215 pages unread.

We are told that if he reads 5 pages per day in how many days would he be done with the 215 pages left.

to solve for the number of days left, we have to divide  215 by 5

that is

=215/5

=43 days

So Jared needs 43 days to read the 215 pages left and return the book to the Lilbrary.

The average speed is 12.29 km/hr

The formula used to calculate average speed is

= distance/time

The first step is to calculate the total distance

Distance A + Distance B

= 42 + 44

= 86

The next step is to calculate the total time spent during the journey

= Time A + Time B

= 3 + 4

= 7

The average speed can be calculated as follows

Average speed= 86/7

= 12.29

Hence the average speed is 12.29 km/hr

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Answer:

JRQ = 56

Step-by-step explanation:

SRQ - SRJ = JRQ

166 - 110 = 56

Answer: -5-2x

Step-by-step explanation: