Ask question

Ask question

All categories

2 years ago

12

For which of the following sample sizes would it not be possible to estimate the mean of a population from the mean and standard

deviation of a sample of that population? A. 50 B. 200 C. 100 D. 5

1 answer:

Harman [31]2 years ago

4 0

Answer:

i would say a hope this helps!

Step-by-step explanation:

You might be interested in

Evaluate the following expression 1/3^2

NISA [10]

Answer:

1/9

Step-by-step explanation:

1/3*1/3=1/9

6 0

3 years ago

First, rewrite 14/25 and 11/20 so that they have a common denominator. Then, use <, =, >

muminat

Answer: 14/25 = 56/100

11/20 = 55/100

14/25 > 11/20

Step-by-step explanation:

The least common multiple of 20 and 25 is 100.

(100 = 20*5, 25*4)

So we can take the common denominator 100.

14*4/25*4 =56/100. ∴14/25 = 56/100

11*5/20*5 =55/100. ∴11/20 = 55/100

56>55

∴56/100 > 55/100

∴14/25 > 11/20

Hope it's good;)

7 0

3 years ago

Can someone please help me with number 2?I don't know what I did wrong.

Dmitry [639]

Part A

Let's say point P is the starting point and point Q is the endpoint

x = one-way distance from P to Q, and vice versa

The goal is to find x, then compute 2x to find the round trip distance traveled.

We'll use this idea

distance = rate*time

which solves to

time = distance/rate

So when going from P to Q, the driver is going 70 mph and travels x miles

So the driver does this for distance/time = x/70 hours.

When going back, the driver slows down to 55 mph so the time taken here is x/55 hours.

The total time values add to x/70 + x/55 hours

Set this equal to the total driving time of 7 hours and solve for x

x/70 + x/55 = 7

70*55*(x/70 + x/55) = 70*55*7

70*55*(x/70) + 70*55*(x/55) = 26,950

55x + 70x = 26,950

125x = 26,950

x = (26,950)/125

x = 215.6 which is the one-way distance in miles

which then means,

2x = 2*215.6 = 431.2

Therefore, the total distance traveled is 431.2 miles

<h3>Answer: 431.2 miles</h3>

=========================================================

Part B

To find the duration of each trip, we simply need to evaluate x/70 and x/55. Those are the durations when going 70 mph and 55 mph respectively. These durations are measured in hours.

x/70 = (215.6)/70 = 3.08

x/55 = (215.6)/55 = 3.92

Note how 3.08+3.92 = 7 to help verify the answers.

<h3>Answers:</h3>

When going 70 mph, it takes about 3.08 hours
When going 55 mph, it takes about 3.92 hours

6 0

3 years ago

College students average 8.6 hours of sleep per night with a standard deviation of 35 minutes. If the amount of sleep is normall

Soloha48 [4]

Answer:

4.27%

Step-by-step explanation:

We have been given that college students average 8.6 hours of sleep per night with a standard deviation of 35 minutes. We are asked to find the probability of college students that sleep for more than 9.6 hours.

We will use z-score formula to solve our given problem.

$z=\frac{x-\mu}{\sigma}$

z = z-score,

x = Random sample score,

$\mu$ = Mean,

$\sigma$ = Standard deviation.

Before substituting our given values in z-score formula, we need to convert 35 minutes to hours.

$35\text{ min}=0.58\text{ Hour}$

$z=\frac{9.6-8.6}{0.58}$

$z=\frac{1}{0.58}$

$z=1.72$

Now, we need to find $P(z>1.72)$ .

Using formula $P(z>a)=1-P(z$ , we will get:

$P(z>1.72)=1-P(z$

Using normal distribution table, we will get:

$P(z>1.72)=1-0.95728$

$P(z>1.72)=0.04272$

$0.04272\times 100\%=4.272\%$

Therefore, 4.27% of college students sleep for more than 9.6 hours.

7 0

3 years ago

John has a job selling souvenirs on a football stadium. He earns $10 per game plus $0.25 dollars for each souvenir he sells. How

Ahat [919]

Answer:

He needs to sell 100 souvenirs

Step-by-step explanation:

We want to know the number of souveniers John has to sell

Let the number of souveniers he sold at the game be s

At a rate of $0.25 per souvenier, the amount earned on souveniers for s souveniers will be:

$0.25 \times s =0.25s$

Now, if we added this to the amount he earns per game, we will have the total $35 earned for working at one game.

Thus, mathematically:

$0.25s + 10 = 35 \\ 0.25s = 35 - 10 \\ 0.25s = 25 \\ s = \frac{25}{0.25} \\ s = 100$

7 0

2 years ago