Write a division that represents the question: how many 3/8s are in 5/4?

In a test (+5) marks are given for every correct answer and (-2) marks are given for every incorrect answer . Roy answered all t

katovenus [111]

Answer:

20 questions

Step-by-step explanation:

Given

$Correct \Marks= +5$

$Incorrect\ Marks= -2$

$Score\ Obtained = 30$

$Number\ of\ correct\ answers = 10$

Required

Number of questions answered

First, we need to get the total correct marks obtained by Roy

This is calculated by multiplying the correct marks by number of correct answers

$Total = +5 * 10$

$Total = +50\ marks$

Subtract this from the total scores obtained; This gives the total incorrect answer obtained by Roy

$Incorrect = Scores\ Obtained - Total$

$Incorrect = 30 - (+50)$

Open bracket

$Incorrect = 30 - 50$

$Incorrect = -20$

Divide this by -2 to get the number of incorrect answers

$Incorrect\ Answers = \frac{-20}{-2}$

$Incorrect\ Answers = 10$

Add this to the number of correct answers to give the total number of question answered

$Total = Correct\ Answers + Incorrect\ Answers$

$Total = 10 + 10$

$Total = 20$

<em>Hence, Roy answered a total of 20 questions</em>

3 0

2 years ago

In 36 days a girl spent 18 dollars. On average, what did she spend daily?

ale4655 [162]

On average, she spent 18/36 = 0.5$

3 0

2 years ago

A radio station claims that the amount of advertising per hour of broadcast time has an average of 13 minutes and a standard dev

zimovet [89]

Answer:

$Z = 3.33$

Step-by-step explanation:

Z-score:

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 question:

$\mu = 13, \sigma = 1.2$

You listen to the radio station for 1 hour, at a randomly selected time, and carefully observe that the amount of advertising time is equal to 17 minutes. Calculate the z-score for this amount of advertising time.

We have to find Z when X = 17. So

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

$Z = \frac{17 - 13}{1.2}$