Mathematics, 21.03.2020 08:53, alannaamarriee

A humanities professor assigns letter grades on a test according to the following scheme. A: Top 12% of scores B: Scores below the top 12% and above the bottom 64d% C: Scores below the top 366% and above the bottom 23#% D: Scores below the top 77w% and above the bottom 7%7% F: Bottom 7%7% of scores Scores on the test are normally distributed with a mean of 77.877.8 and a standard deviation of 8.58.5. Find the minimum score required for an A grade. Round your answer to the nearest whole number, if necessary.

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answered: emopandabogard4296

The minimum score required for an A grade is 88.

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

$\mu = 77.8, \sigma = 8.5$

Find the minimum score required for an A grade.

Top 12%, which is at least the 100-12 = 88th percentile, which is the value of X when Z has a pvalue of 0.88. So it is X when Z = 1.175.

$Z = \frac{X - \mu}{\sigma}$

$1.175 = \frac{X - 77.8}{8.5}$

X - 77.8 = 1.175*8.5

X = 87.8

Rounding to the nearest whole number

The minimum score required for an A grade is 88.

answered: andrew8228

the minimum score required for an A grade is 88.

Step-by-step explanation:

Since the scores on the test are normally distributed, we would apply the formula for normal distribution which is expressed as

z = (x - µ)/σ

Where

x = scores on the test.

µ = mean score

σ = standard deviation

From the information given,

µ = 77.8

σ = 8.5

The probability value for the top 12% of the scores would be (1 - 12/100) = (1 - 0.13) = 0.88

Looking at the normal distribution table, the z score corresponding to the probability value is 1.18

Therefore,

1.18 = (x - 77.8)/8.5

Cross multiplying by 8.5, it becomes

1.18 × 8.5 = x - 77.8

10.03 = x - 77.8

x = 10.03 + 77.8

x = 88 to the nearest whole number

answered: Guest

(d)

step-by-step explanation:

given: the line in the graph passes through points (5,30) and (6,26).

then, the equation of line is:

$y-y_{1}=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}(x-x_{1})$

$y-30=\frac{26-30}{6-5}(x-5)$

$y-30=-4(x-5)$

$y-30=-4x+20$

$y=-4x+50$

now, put y=a(n) and x=n,

$a(n)=-4n+50$

$a(n)=-4n+46+4$

$a(n)=46-(n-1){\times}4$

hence, option d is correct.

Ascientist cools some water at a constant rate. the graph and table show how the temperature of the

answered: Guest

the most boring thing ever written

step-by-step explanation:

i am writing something. yes, i plan to make it the most boring thing ever written. i go to the store. a car is parked. many cars are parked or moving. some are blue. some are tan. they have windows. in the store, there are items for sale. these include such things as soap, detergent, magazines, and lettuce. you can enhance your life with these products. soap can be used for bathing, be it in a bathtub or in a shower. apply the soap to your body and rinse. detergent is used to wash clothes. place your dirty clothes into a washing machine and add some detergent as directed on the box. select the appropriate settings on your washing machine and you should be ready to begin. magazines are stapled reading material made with glossy paper, and they cover a wide variety of topics, ranging from news and politics to business and stock market information. some magazines are concerned with more recreational topics, like sports card collecting or different kinds of hairstyles. lettuce is a vegetable.