NEED HELP PLEASE WHAT IS THE NUMBER IN THE QUESTION MARK

MariettaO [177]

Answer:

0.7969

Step-by-step explanation:

Given that: A sample of size n= 49 is obtained. The population mean is m= 80 and the population standard deviation is s = 14.

The z score measures the number of standard deviation by which the raw sore is above or below the mean. It is given by the equation:

$z=\frac{x-m}{\frac{s}{\sqrt{n} } }$

For x = 78.3, the z score is:

$z=\frac{x-m}{\frac{s}{\sqrt{n} } }=\frac{78.3-80}{\frac{14}{\sqrt{49} } } =-0.85$

For x = 85.1, the z score is:

$z=\frac{x-m}{\frac{s}{\sqrt{n} } }=\frac{85.1-80}{\frac{14}{\sqrt{49} } } =2.55$

P(78.3<x<85.1) = P(-0.85<z<2.55) = P(z<2.55) - P(z<-0.85) = 0.9946 - 0.1977 = 0.7969

7 0

4 years ago

Read 2 more answers

I need help with this

Marina CMI [18]

Yea I’m not sure more info?

6 0

3 years ago

A plane has an airspeed of 111 km/h. It is flying on a bearing of 79 degrees while there is a 25 km/h wind out of the northeast

qwelly [4]

Answer: Ground Speed = 91 km/hr, Bearing = 189°

Step-by-step explanation:

Step 1: Draw a picture (see attached) to determine the angle between the given vectors. Notice that I moved the wind vector 180° so the head of the wind vector would line up with the tail of the plane vector. This created an angle of 34° between the plane and wind vectors. Why?

the dashed line is 45°
79° (plane) - 45° (wind) = 34°

Step 2: Solve for the length of the resultant vector using Law of Cosines

c² = a² + b² - ab cos C

c² = (111)² + (25)² - (111)(25) cos 34°

c² = 12,946 - 4601

c² = 8345

c = 91

Ground speed is 91 km/hr

Step 3: Solve for the bearing of the resultant vector using Law of Sines

$\dfrac{sin\ A}{a}=\dfrac{sin\ C}{c}$

$\dfrac{sin\ A}{25}=\dfrac{sin\ 34}{91}$

$sin\ A=\dfrac{25\ sin\ 34}{91}$

$A=sin^{-1}\bigg(\dfrac{25\ sin\ 34}{91}\bigg)$

A = 9°

Reminder that we moved the wind vector 180° to create the resultant vector so we need to add 180° to our answer.

Bearing = A + 180°

= 9° + 180°

= 189°

7 0

3 years ago

You bought a freezer that is 2 geet wide, 4 feet long and 30 inches deep. What is the capacity or volume of the freezer?

inna [77]

34,560 cubic inches I think,
2ft= 24in
4ft= 48in
30in x 24in x 48in = 34,560

8 0

3 years ago

Read 2 more answers

34. For the following exercises, given each set of information, find a linear equation satisfying the conditions, if possible.

skad [1K]

Answer:

The linear equation for the line which passes through the points given as (-1,4) and (5,2), is written in the point-slope form as $y=\frac{1}{3} x-\frac{13}{3}$ .

Step-by-step explanation:

A condition is given that a line passes through the points whose coordinates are (-1,4) and (5,2).

It is asked to find the linear equation which satisfies the given condition.

Step 1 of 3

Determine the slope of the line.

The points through which the line passes are given as (-1,4) and (5,2). Next, the formula for the slope is given as,

$m=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}$

Substitute 2&4 for $y_{2}$ and $y_{1}$ respectively, and $5 \&-1$ for $x_{2}$ and $x_{1}$ respectively in the above formula. Then simplify to get the slope as follows,