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3 years ago

5

Recently, Frank took a one-hundred question aptitude test where each correct answer scored 5 points, each incorrect answer score

d -2 points, and each question not answered scored zero points. Frank answered 80 questions and scored 232 points. How many questions did he answer correctly?

2 answers:

Neporo4naja [7]3 years ago

8 0

Answer:

56 questions were correctly answered by Frank.

Step-by-step explanation:

Let Frank answered the number of correct questions = x

Let wrong answers given by Frank = y

By statement 1 "Frank answered 80 questions".

Equation will be x + y = 80 ---------(1)

Statement 2 "Frank scored 232 points."

equation will be 5x - 2y = 232 ------(2)

We have to calculate number of correct answers.

Multiply equation (1) by (2) then add it to equation (1).

(2x + 2y) + (5x - 2y) = 160 + 232

7x = 392

x = 56

Therefore, 56 questions were correctly answered by Frank.

Lyrx [107]3 years ago

3 0

Im guessing he answered 30 correct, let me know if im correct

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4 years ago

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Answer:

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Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

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Now, we have to find a value of T, which is found looking at the t table, with 11 degrees of freedom(y-axis) and a confidence level of $1 - \frac{1 - 0.95}{2} = 0.975$ . So we have T = 2.201

The margin of error is:

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The upper end of the interval is the sample mean added to M. So it is 19.2 + 1.3 = 20.5 students

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Answer:

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Step-by-step explanation:

Previous concepts

Analysis of variance (ANOVA) "is used to analyze the differences among group means in a sample".

The sum of squares "is the sum of the square of variation, where variation is defined as the spread between each individual value and the grand mean"

Solution to the problem

The hypothesis for this case are:

Null hypothesis: $\mu_{A}=\mu_{B}=\mu_{C}= \mu_D$

Alternative hypothesis: Not all the means are equal $\mu_{i}\neq \mu_{j}, i,j=A,B,C,D$

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$SST=SS_{between}+SS_{within}$

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$p_v= 0.01$

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b. at least some, but not all, of the gestation periods across all four species are the same

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4 years ago

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see explanation

Step-by-step explanation:

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3 years ago

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Sergio [31]

Answer:

Please check the explanation.

Step-by-step explanation:

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3 years ago