Please answer this! 100 Points!

2. The Welcher Adult Intelligence Test Scale is composed of a number of subtests. On one subtest, the raw scores have a mean of

IgorC [24]

Answer:

a) 37.31 b) 42.70 c) 0.57 d) 0.09

Step-by-step explaanation:

We are regarding a normal distribution with a mean of 35 and a standard deviation of 6, i.e., $\mu$ = 35 and $\sigma$ = 6. We know that the probability density function for a normal distribution with a mean of $\mu$ and a standard deviation of $\sigma$ is given by

$f(x) = \frac{1}{\sqrt{2\pi}\sigma}\exp[-\frac{(x-\mu)^{2}}{2\sigma^{2}}]$

in this case we have

$f(x) = \frac{1}{\sqrt{2\pi}6}\exp[-\frac{(x-35)^{2}}{2(6^{2})}]$

Let $X$ be the random variable that represents a row score, we find the values we are seeking in the following way

a) we are looking for a number $x_{0}$ such that

$P(X\leq x_{0})$ = $\int\limits^{x_{0}}_{-\infty} {f(x)} \, dx = 0.65$ , this number is $x_{0}$ =37.31

you can find this answer using the R statistical programming languange and the instruction qnorm(0.65, mean = 35, sd = 6)

b) we are looking for a number $x_{1}$ such that

$P(X\leq x_{1})$ = $\int\limits^{x_{1}}_{-\infty} {f(x)} \, dx = 0.9$ , this number is $x_{1}$ =42.70

you can find this answer using the R statistical programming languange and the instruction qnorm(0.9, mean = 35, sd = 6)

c) we find this probability as

$P(28\leq X\leq 38)$ = $\int\limits^{38}_{28} {f(x)} \, dx = 0.57$

you can find this answer using the R statistical programming languange and the instruction pnorm(38, mean = 35, sd = 6) -pnorm(28, mean = 35, sd = 6)

d) we find this probability as

$P(41\leq X\leq 44)$ = $\int\limits^{44}_{41} {f(x)} \, dx = 0.09$

you can find this answer using the R statistical programming languange and the instruction pnorm(44, mean = 35, sd = 6) -pnorm(41, mean = 35, sd = 6)

6 0

4 years ago

Read 2 more answers

you place a cup of 200f coffee on a table in a room that is 67f and 10 minutes later it is 195f. approximately how long will it

kompoz [17]

Newton's law of cooling says the rate of change of temperature is proportional to the difference between the object's temperature and the temperature of the environment.

Here, the object starts out at 200 °F, which is 133 °F greater than the environment temperature. 10 minutes later, the object is 195 °F, so is 128 °F greater than the environment. In other words, the temperature difference has decayed by a factor of 128/133 in 10 minutes.

The solution to the differential equation described by Newton's Law of Cooling can be written as the equation
T(t) = 67 + 133*(128/133)^(t/10)
where T is the object's temperature in °F and t is the time in minutes from when the object was placed in the 67 °F environment.

The equation
T(t) = 180
can be solved analytically, but it can be a bit easier to solve it graphically. A graphing calculator shows it takes 42.528 minutes for the temperature of the coffee to reach 180 °F.

7 0

3 years ago

A total of 543718 visitors went to a theme park during August and September . if 321654 visitors went to the theme park in augus

docker41 [41]

I think its 222064 i'm pretty sure it's correct

8 0

3 years ago

A bull had horns that measured 98 inches across. what is this length in feet and inches?

zhenek [66]

HI Spowell1171! Here's how you do this:

12 in = 1 ft

98 ÷ 12 = 8 R 2

So, now you have 8 R2. This means you have 8 feet and 2 inches. So your answer is 8 feet and 2 inches. Hope I helped!

3 0

3 years ago

The regular price of a code is $32 it is on sale at 25% off the sales tax is 6.5% what is the final cost of code

Nutka1998 [239]

Answer:

$25.56

Step-by-step explanation:

first find the discount

32 • 0.25 = 8

32 - 8= 24

find the tax

24 • 0.065 = 1.56

24 +1.56 = 25.56

so the final price is $ 25.56

3 0

3 years ago

Read 2 more answers