There are 8 brooms in a janitors closet . What is the ratio of the number of mops to the number of brooms

Many states assess the skills of their students in various grades. One program that is available for this purpose is the Nationa

Nataly [62]

Answer:

A score of 314 is needed to be in the top 25% of students who take this exam.

Step-by-step explanation:

We are given that one of the tests provided by the NAEP assesses the reading skills of twelfth-grade students. In recent years, the national mean score was 289 and the standard deviation was 37.

Let X = <u><em>scores of the tests provided by the NAEP</em></u>

The z-score probability distribution for the normal distribution is given by;

Z = $\frac{X-\mu}{\sigma}$ ~ N(0,1)

where, $\mu$ = national mean score = 289

$\sigma$ = standard deviation = 37

Now, we have to find how high a score is needed to be in the top 25% of students who take this exam, that means;

P(X > x) = 0.25 {where x is the required score}

P( $\frac{X-\mu}{\sigma}$ > $\frac{x-289}{37}$ ) = 0.25

P(Z > $\frac{x-289}{37}$ ) = 0.25

In the z table, the critial value of z that represents the top 25% of the area is given as 0.6745, that is;

$\frac{x-289}{37}=0.6745$

${x-289}=0.6745\times 37$

x = 289 + 24.96 = 313.96 ≈ 314

Hence, a score of 314 is needed to be in the top 25% of students who take this exam.

7 0

3 years ago

How many solutions does the following equation have? 5 x + 8 − 7 x = − 4 x + 1 5x+8−7x=−4x+15, x, plus, 8, minus, 7, x, equals,

UNO [17]

Answer: There is one valid solution to the equation 5x + 8 - 7x = -4x + 1, x = -3.5.

Step-by-step explanation:

8 0

2 years ago

Almost all medical schools in the United States require students to take the Medical College Admission Test (MCAT). To estimate

Leviafan [203]

Answer:

Probability of having student's score between 505 and 515 is 0.36

Given that z-scores are rounded to two decimals using Standard Normal Distribution Table

Step-by-step explanation:

As we know from normal distribution: z(x) = (x - Mu)/SD

where x = targeted value; Mu = Mean of Normal Distribution; SD = Standard Deviation of Normal Distribution

Therefore using given data: Mu (Mean) = 510, SD = 10.4 we have z(x) by using z(x) = (x - Mu)/SD as under:

In our case, we have x = 505 & 515

Approach 1 using Standard Normal Distribution Table:

z for x=505: z(505) = (505-510)/10.4 gives us z(505) = -0.48

z for x=515: z(515) = (515-510)/10.4 gives us z(515) = 0.48

Afterwards using Normal Distribution Tables and rounding the values to two decimals we find the probabilities as under:

P(505) using z(505) = 0.32

Similarly we have:

P(515) using z(515) = 0.68

Now we may find the probability of student's score between 505 and 515 using:

P(505 < x < 515) = P(515)-P(505) = 0.68 - 0.32 = 0.36

PS: The standard normal distribution table is being attached for reference.

Approach 2 using Excel or Google Sheets:

P(x) = norm.dist(x,Mean,SD,Commutative)

P(505) = norm.dist(505,510,10.4,1)

P(515) = norm.dist(515,510,10.4,1)

Probability of student's score between 505 and 515= P(515) - P(505) = 0.36

Download pdf

6 0

3 years ago

In a sample of people on the school board 2 out of 5 were in favor of a new high school being built if 3,500 people vote in the

ioda

Answer:

Just about 2100 people

Step-by-step explanation:

2 out of 5 is 60% and 7*5 is 35 so if you multiply 7 by 3 then you get 21 and if you multiply that by 100 then you get 2100

7 0

3 years ago

Read 2 more answers

It's nothing new: Let's recap rounding to the nearest 100<br>61566=<br>70284=

kap26 [50]

Answer:

Step-by-step explanation:

61566= 61600

70284= 70300

<h2><em>hope this helps comment if/if not </em></h2>

8 0

2 years ago