A market analyst is curious what proportion Los Angeles residents have a landline telephone. A survey of 200

Given: ∆ABC, m∠C = 90°

Galina-37 [17]

Answer: 16 units

Step-by-step explanation:

Given that in triangle ABC, m∠C=90,

it means m∠A +∠B= m∠BAC + m∠ABC = 90

m∠ABC = 90 - m∠BAC

Also given that;m∠BAC = 2m∠ABC

So,

m∠BAC = 2(90 - m∠BAC) = 180 - 2m∠BAC

m∠BAC +2m∠BAC = 180

3m∠BAC = 180

m∠BAC=180/3 = 60

m∠ABC = 60/3 = 30

thus,ΔBAC is a 30-60-90 right triangle, in which the ratio of the side lengths is 1:√3:2AC:BC=1:√3, AC=BC/√3BC=24, So,

AC=24/√3=8√3AL bisects angle A =>m∠LAC=30

ΔALC is a 30-60-90 right triangle, in which the ratio of the side lengths is 1:√3:2AC:AL=√3:2AL=2AC/√3=2x8√3/√3=16

8 0

3 years ago

At NC State University, 16.4% of the undergraduate classes have more than 50 students. If a random sample of 200 undergraduate c

Lena [83]

Answer:

We need to check the conditions in order to use the normal approximation.

$np=200*0.164=32.8 \geq 10$

$n(1-p)=200*(1-0.164)=167.2 \geq 10$

$p \sim N(p,\sqrt{\frac{p(1-p)}{n}})$

The mean is given by:

$p =0.164$

And the deviation is given by:

$\sigma_{p}= \sqrt{\frac{0.164*(1-0.164)}{200}}= 0.0262$

So then the correct options for this case are:

The sampling distribution will be approximately normal.

The mean of the sampling distribution will be 16.4%.

The standard deviation of the sampling distribution will be 0.0262.

Step-by-step explanation:

Previous concepts

The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".

Let X the random variable of interest, on this case we now that:

$X \sim Binom(n=200, p=0.164)$

The probability mass function for the Binomial distribution is given as:

$P(X)=(nCx)(p)^x (1-p)^{n-x}$

Where (nCx) means combinatory and it's given by this formula:

$nCx=\frac{n!}{(n-x)! x!}$

We need to check the conditions in order to use the normal approximation.

$np=200*0.164=32.8 \geq 10$

$n(1-p)=200*(1-0.164)=167.2 \geq 10$

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{p(1-p)}{n}})$

The mean is given by:

$p =0.164$

And the deviation is given by:

$\sigma_{p}= \sqrt{\frac{0.164*(1-0.164)}{200}}= 0.0262$

So then the correct options for this case are:

The sampling distribution will be approximately normal.

The mean of the sampling distribution will be 16.4%.

The standard deviation of the sampling distribution will be 0.0262.

6 0

3 years ago

Hii please help i’ll give brainliest!!

AnnZ [28]

Answer:

The acceleration of golf ball will be greater than the bowling ball.

Step-by-step explanation:

As the golf ball is light thing that will travel far but the bowling ball is heavier than the golf ball.So the acceleration of the golf ball will be more.

3 0

3 years ago

Read 2 more answers

Hexagon DEFGHI is translated 8 units down and 3 units to the right. If the coordinates of the pre-image of point F are

Zarrin [17]

The coordinates of F' is (-9 + 3, 2 - 8) = (-6, -6)

6 0

4 years ago

Read 2 more answers

The image of the point (7,-4) under a translation is (12,-5). Find the coordinates

Afina-wow [57]

The translation is right 5, down 1, AKA (x+5, y-1). The original coordinate of the point given is (-8,-3). Use the same translation so ((-8 + 5), (-3 - 1)) = (-3,-4)

3 0

3 years ago