Brynn rides her bike 84 miles in 4 hours.<br> a. Create a ratio of Brynn's miles per hour.

One brand of cookies is sold in three different box sizes: small, medium, and large. The small box has half the volume of the me

lozanna [386]

Answer:

a

Step-by-step explanation:

6 0

2 years ago

(b) A department store has 7,000 charge accounts. The comptroller takes a random sample of 36 of

galben [10]

Answer:

a.0.8664

b. 0.23753

c. 0.15866

Step-by-step explanation:

The comptroller takes a random sample of 36 of the account balances and calculates the standard deviation to be N42.00. If the actual mean (1) of the account balances is N175.00, what is the probability that the sample mean would be between

a. N164.50 and N185.50?

b. greater than N180.00?

c. less than N168.00?

We solve the above question using z score formula

z = (x-μ)/σ/√n where

x is the raw score,

μ is the population mean = N175

σ is the population standard deviation = N42

n is random number of sample = 36

a. Between N164.50 and N185.50?

For x = N 164.50

z = 164.50 - 175/42 /√36

z = -1.5

Probability value from Z-Table:

P(x = 164.50) = 0.066807

For x = N185.50

z = 185.50 - 175/42 /√36

z =1.5

Probability value from Z-Table:

P(x=185.50) = 0.93319

Hence:

P(x = 185.50) - P(x =164.50)

= 0.93319 - 0.066807

= 0.866383

Approximately = 0.8664

b. greater than N180.00?

x > N 180

Hence:

z = 180 - 175/42 /√36

z = 5/42/6

z = 5/7

= 0.71429

Probability value from Z-Table:

P(x<180) = 0.76247

P(x>180) = 1 - P(x<180) = 0.23753

c. less than N168.00?

x < N168.

z = 168 - 175/42 /√36

z = -7/42/6

z = -7/7

z = -1

Probability value from Z-Table:

P(x<168) = 0.15866

4 0

2 years ago

A random sample of 28 statistics tutorials was selected from the past 5 years and the percentage of students absent from each on

SVEN [57.7K]

Answer:

Step-by-step explanation:

Hello!

X: number of absences per tutorial per student over the past 5 years(percentage)

X≈N(μ;σ²)

You have to construct a 90% to estimate the population mean of the percentage of absences per tutorial of the students over the past 5 years.

The formula for the CI is:

X[bar] ± $Z_{1-\alpha /2}$ * $\frac{S}{\sqrt{n} }$

⇒ The population standard deviation is unknown and since the distribution is approximate, I'll use the estimation of the standard deviation in place of the population parameter.

Number of Absences 13.9 16.4 12.3 13.2 8.4 4.4 10.3 8.8 4.8 10.9 15.9 9.7 4.5 11.5 5.7 10.8 9.7 8.2 10.3 12.2 10.6 16.2 15.2 1.7 11.7 11.9 10.0 12.4

X[bar]= 10.41

S= 3.71

$Z_{1-\alpha /2}= Z_{0.95}= 1.645$

[10.41±1.645* $(\frac{3.71}{\sqrt{28} } )$ ]

[9.26; 11.56]

Using a confidence level of 90% you'd expect that the interval [9.26; 11.56]% contains the value of the population mean of the percentage of absences per tutorial of the students over the past 5 years.

I hope this helps!

7 0

2 years ago

the table shows the number of minutes Tim has for lunch and study hall. he calculates that these two periods account for 18% of

EleoNora [17]

Tim spends 500 minutes at the school.

Step-by-step explanation:

Given,

Time for lunch = 45 minutes

Time for study hall = 45 minutes

Total = 45+45 = 90 minutes

This represents 18% of the total minutes Tim spend at school.

Let,

x be the total minutes Tim spend at school.

18% of x = 90 minutes

$\frac{18}{100}x=90\\\\0.18x=90$

Dividing both sides by 0.18

$\frac{0.18x}{0.18}=\frac{90}{0.18}\\x=500$

Tim spends 500 minutes at the school.

Keywords: percentage, division

Learn more about division at:

#LearnwithBrainly

5 0

2 years ago

In a recent survey of dog owners, it was

siniylev [52]

Answer:

1749

Step-by-step explanation:

You would set up a proportion that says 901/x = 34/100. You would cross multiply to get that 34x = 90100. You would divide 90100 by 34 to get 2650. Then do 2650 - 901 to get 1749.

6 0

2 years ago

Brynn rides her bike 84 miles in 4 hours. a. Create a ratio of Brynn's miles per hour.