Ask question

Ask question

All categories

3 years ago

8

A random sample of students at North High School were polled on whether they prefer a 15-minute break between classes in the mor

ning or in the afternoon. The results are shown in the frequency table.
A 4-column table with 4 rows. The first column has no label with entries 10th, 11th, 12th, total. The second column is labeled morning with entries 21, 16, 19, 56. The third column is labeled afternoon with entries 17, 25, 20, 62. The fourth column is labeled total with entries 38, 41, 39, 118.
What is the joint relative frequency for 11th graders who want the break in the afternoon? Round to the nearest percent

2 answers:

pav-90 [236]3 years ago

8 0

Answer:

1. 10.1%

2. 16.5%

3. 58.9%

4.41.1%

Step-by-step explanation:

i just did the question

ioda3 years ago

3 0

Answer:

21%

Step-by-step explanation:

Trust me, it just is. :))))

You might be interested in

Plot the point (3/2,-9/2)

fiasKO [112]

Answer:

You need a graph, but x = 3/2 and y = -9/2

Step-by-step explanation:

You need a graph to plot points. Here is a graph:

https://www.wolframalpha.com/input/?i=Plot+the+point+(3%2F2,-9%2F2)

Anyways, 3/2 = 1.5 and -9/2 = -4.5, so that is why it shows those points on the graph.

1.5 is on the x-axis while -4.5 is on the y axis.

4 0

3 years ago

A common inhabitant of human intestines is the bacterium Escherichia coli, named after the German pediatrician Theodor Escherich

Bess [88]

Answer:

a). k = 2.0794

b). $A_{t}=A_{0}(2^{3t} )$

c). 13107200 cells

d). rate of growth after 6 hours = 27255112

e). 4.76 hours

Step-by-step explanation:

From the formula of bacterial population,

$A_{t}=A_{0}e^{kt}$

Where $A_{t}$ = Bacterial population after time t

$A_{0}$ = Initial population

k = relative growth factor

t = duration or time

a). For $A_{t}=2\times 50=100$ cells

and $A_{0}=50$ cells

Time t = 20 minutes = $\frac{1}{3}$ hours

Now we plug in these values in the formula,

100 = $50(e^{\frac{k}{3}})$

$e^{\frac{k}{3}}=2$

By taking natural log on both the sides of the equation,

$\frac{k}{3}(lne)=ln(2)$

k = 3ln(2) = 2.0794

b). To get the expression we will plug in the value of k in the formula.

$A_{t}=A_{0}e^{kt}$

Since k = 3ln(2)

$A_{t}=A_{0}e^{3t(ln2)}$

Let y = $e^{3t(ln2)}$

By taking natural log on both the sides of the equation,

lny = $ln(e^{3t(ln2)} )$

lny = 3t(ln2)ln(e)

ln(y) = 3t(ln2)

ln(y) = $ln(2)^{3t}$

y = $2^{3t}$

Now our expression will be $A_{t}=A_{0}(2^{3t} )$

c). Number of cells after t = 6 hours

$A_{6}=50(2^{3\times 6} )$

$A_{6}=50(2^{18})$

$A_{6}=50\times (262144)=13107200$

d). We can get the rate of growth by finding derivative of the expression

$\frac{d}{dt}(A_{t})=\frac{d}{dt}[A_{0}(e^{kt}})]$

= $A_{0}[ke^{kt}]$

Now $\frac{d}{dt}(A_{6})=k.A_{6}$

= 2.0794×13107200

= 27255112

e) From the given formula,

$A_{t}=A_{0}(2^{3t} )$

$1000000=50(2^{3t} )$

$2^{3t}=20000$

3t(ln2) = ln(20000)

t = $\frac{ln(20000)}{3(ln2)}$

t = $\frac{9.90349}{2.07944}=4.76$ hours

3 0

3 years ago

NEED HELP FAST PLZ!!!!!!!

finlep [7]

Answer:

y = {-2, 6}

Step-by-step explanation:

The fastest help is afforded by a graphing calculator. It shows you the y-values at the points of intersection are -2 and +6.

5 0

4 years ago

You need to have $20,000 for a down payment on a house 6 in years. If you can earn an annual interest rate of 4.2 percent, how m

Alexxandr [17]

Answer: you have to deposit $15625 today

Step-by-step explanation:

Assuming the interest is compounded annually. We would apply the formula for determining compound interest which is expressed as

A = P(1+r/n)^nt

Where

A = total amount in the account at the end of t years

r represents the interest rate.

n represents the periodic interval at which it was compounded.

P represents the principal or initial amount deposited

From the information given,

A = $20000

r = 4.2% = 4.2/100 = 0.042

n = 1 because it was compounded once in a year.

t = 6 years

Therefore,.

20000 = P(1 + 0.042/1)^1 × 6

20000 = P(1.042)^6

20000 = 1.28P

P = 20000/1.28

P = $15625

6 0

4 years ago

Please help!!!!!

KATRIN_1 [288]

Answer:

50+ 20x= y

25+ 40x= y

Explanation:

For Billy and Susie, the starting values are $50 and $25. You simply add that to the money saved per week ($20 and $40).

x= number of weeks

6 0

3 years ago

Read 2 more answers