A toothpaste advertises that 30% of stains are removed after 1 week. As Alexa is brushing her teeth, she thinks "after 2 weeks, 60% of stains will be gone, and 90% after three weeks".

Using this reasoning, what percent of stains will be gone after four weeks? Does this result make sense? Why or why not?

Answer:

122

Step-by-step explanation:

122 + 58 = 180

Answer:

x=122°

Step-by-step explanation:

58° and x form a straight angle, which is 180°.

x+58°=180°

x=180°-58°=122°

Answer:

F $1800

Step-by-step explanation:

First, converting R percent to r a decimal

r = R/100 = 4%/100 = 0.04 per year,

then, solving our equation

I = 15000 × 0.04 × 3 = 1800

I = $ 1,800.00

The simple interest accumulated

on a principal of $ 15,000.00

at a rate of 4% per year

for 3 years is $ 1,800.00.

Answer:

F. $1800

Step-by-step explanation:

Simple interest means that a percent of the initial amount will be paid back each year, this amount will not change from year to year. To calculate the simple interest over a given unit of time, multiply the amount by the interest rate in decimal form, then multiply that value by the time span that this was taken over. The result will be the amount earned.

The following formula can be used to describe this scenario,

[tex]simple\ interest=(time)((amount)(interest\ rate))[/tex]

Substitute,

[tex]=(3)((15000)(4))[/tex]

To convert a percent to decimal form, divide the percent by (100)

[tex]=(3)((15000)(0.04))[/tex]

[tex]=(3)(600)\\\\=1800[/tex]

Answer:

H

Step-by-step explanation:

[tex]\frac{1}{4} + \frac{4}{5} = 1\frac{1}{20}[/tex]

Answer:

Hi, using L.C.M, It will be option H

Answer:

10

Step-by-step explanation:

Answer:

Hello some data related to your question is missing attached below is the missing data

a) we will reject the null hypothesis hence it can be determined that the salary of politicians is greater than that of EMTs through the use of two-sample t procedures. since ( to > critical value )

b) ( 3.819 , 8.5226 )

Step-by-step explanation:

Applying the Given data:

The test hypothesis :

H0 : μ1 = μ2

Ha : μ1 > 2

A) since ( to > critical value ) we will reject the null hypothesis hence it can be determined that the salary of politicians is greater than that of EMTs through the use of two-sample t procedures

B ) construct and interpret

next calculate the SP value

[tex]S^{2} _{p}[/tex] = [tex]\frac{( n1 - 1 )S^{2} _{1} + ( n_{2}- 1 )S^{2} _{2} }{n1 + n2 - 2}[/tex]

where: S1 = 7524 , n1 = 50 , n2 = 100 , S2 = 5551   ( input values into equation above )

∴ [tex]S^{2} _{p}[/tex] = 39354491.3716

hence : [tex]S_{p}[/tex] = 6273.32

next calculate the value of test statistic

to = ( X1 - X2 - Δo ) / Sp [tex]\sqrt{\frac{1}{n1} + \frac{1}{n2} }[/tex]

where: X1 = 61234 , X2 = 54529 , Sp = 6273.32 , n1 = 50 , n2 = 100  ( input values into equation above )

to = 6705 / 1086.5702 = 6.1708

Df ( degree of freedom ) = n1 + n2 - 2 = 148

critical value at ∝ = 0.01  = ± 2.3518  ( using excel function : T.INV(0.01,148) )

hence the confidence Interval

= ( 6.1708 ± 2.3518 )

= ( 3.819 , 8.5226 )

For the table of Mrs. Toguchi the t test for two sample is not justified and the confidence interval for this two values is (6.1708, ±2.3518).

Random sample is the way to choose a number or sample in such a manner that each of the sample of the group has an equal probability to be chosen.

Mrs. Toguchi wants to determine if politicians tend to have higher salaries, on average, than first responders (specifically emergency medical technicians, EMTs).

Independent random samples from each of these two professions were selected and their salaries were recorded. The data are summarized below.

                                   Politicians        EMT's

Mean                            $61,234       $54,529

Standard deviation      $7524          $5551

n                                      50                100

The hypothesis for the test,

[tex]H_0:\mu_1=\mu_2\\H_a:\mu_1 > 2[/tex]

No it is not justifies, as the null hypothesis is rejected.

The pooled estimate of a common population standard deviation can be given as,

[tex]S_p=\sqrt{\dfrac{(n_1-1)S_1^2+(n_2-1)S_2^2}{n_1+n_2-2}}[/tex]

Put the values in the above formula from the table, we get,

[tex]S_p=\sqrt{\dfrac{(50-1)(7524)^2+(100-1)(5551)^2}{50+100-2}}\\S_p=6273.32[/tex]

Use the formula of test statistics for equal variance as,

[tex]t=\dfrac{\overline y_1-\overline y_2-0}{s_p\sqrt{\dfrac{1}{n_1}+\dfrac{1}{n_2}}}[/tex]

Put the values from the table as,

[tex]t=\dfrac{61234-54529-0}{(6263.32)\sqrt{\dfrac{1}{50}+\dfrac{1}{100}}}\\t=6.1708[/tex]

The degree of freedom can be given as,

[tex]DF=100+50-2\\DF=148[/tex]

The critical value for 99 percent interval (0.01) is ±2.3518.

Hence, the confidence interval for this two values is (6.1708, ±2.3518).

Thus, for the table of Mrs. Toguchi the t test for two sample is not justified and the confidence interval for this two values is (6.1708, ±2.3518).

Learn more about the random sample here;

https://brainly.com/question/17831271

Answer:

C IS THE ANSWER

I can't read these but is this a school issued textbook of some sort? I might be able to help if so *MIGHT*

Answer:

DID NOT INCLUDE THE ONES I CANT SEE. 3.A   8.A    9.B    10.B   11.D   12.A   13.A .  14.B   16.D   17.C   18.B    19.A     20.A(Not 100% sure on 20)

Step-by-step explanation:

Dont have time to explain

Answer:its A

Step-by-step explanation:

I ask my teacher so its A

Answer:

x<9

Step-by-step explanation:

Answer:

4

Step-by-step explanation:

Another way to write this is 8/1 x 1/2. Then the answer would be 8/2. Simplify to get 4.

8 × 1/2 = 4!

Calculation steps:

8 ×

1

2

= 8 ×

1

2

=

8 × 1

1 × 2

=

8

2

=

8 ÷ 2

2 ÷ 2

= 4

Answer:

c

Step-by-step explanation:

Answer:

.......117. hope it helps

We are given the Geometric Series:

[tex]2 + \frac{2}{3} + \frac{2}{9} + \frac{2}{27} + \frac{2}{81} + \frac{2}{243} + \frac{2}{729}[/tex]

which can be rewritten as:

[tex]2 + \frac{2}{3} + \frac{2}{3^{2} } + \frac{2}{3^{3}} + \frac{2}{3^{4}} + \frac{2}{3^{5}} + \frac{2}{3^{6}}[/tex]

here, we can see that every term is (1/3) times the last term

Hence, we can say that the common ratio of this Geometric Series is 1/3

Finding the Sum:

We know that the sum of a Geometric Series is:

[tex]S_{n} = \frac{a(r^{n}-1)}{r-1}[/tex]

(where r is the common ratio, a is the first term, and n is the number of terms)

another look at the given Geometric Series tells us that the first term is 2 and the number of terms is 7

plugging these values in the formula, we get:

[tex]S_{n} = \frac{2((1/3)^{7}-1)}{(1/3)-1}[/tex]

[tex]S_{n} = \frac{-1.99}{-0.67}[/tex]

Sₙ = 2.97

Step-by-step explanation:

[tex] \tt2 + \frac{2}{3} + \frac{2}{ {3}^{2} } + \frac{2}{ {3}^{3} } + \frac{2}{ {3}^{4} } + \frac{2}{ {3}^{5} } + \frac{2}{ {3}^{6} } [/tex]

r = [tex]\tt{a_2 \div a_1}[/tex]

r = [tex]\tt{\frac{2}{3} \div 2}[/tex]

r = [tex]\tt{\bold{\frac{1}{3}}}[/tex]

Soo :

[tex] \sf s_n = \frac{a( {r}^{n} - 1) }{r - 1} [/tex]

[tex] \sf s_7 = \frac{2(( \frac{1}{3} ) {}^{7 - 1} - 1) }{( \frac{1}{3} - 1) } [/tex]

[tex] \sf s_7 \approx \bold{ \underline{2.97}}[/tex]

Answer:

5 outfits

Step-by-step explanation:

The number of many different outfits does Sarah have to choose from should be 32.

Since  She can choose from 2 pairs of pants, 8 t-shirts, and 2 pairs of shoes.

So here the number of distinct outfits should be like

[tex]= 2\times 8 \times 2[/tex]

= 32

hence, The number of many different outfits does Sarah have to choose from should be 32.

Learn more about number here: https://brainly.com/question/24604425

Answer:

-3ab, -9x^2 -13x

Step-by-step explanation:

45a^4b^3 - 90a^3b/ 15a^2b

-45ab^2/15a^2b

-3ab

13) (x-7x^2) - (2x^2+14x)

-9x^2 -13x

Answer:

No solution

Step-by-step explanation:

1. Distribute the right side.

8w+5=8w+4

2. This has no solution.

Answer:

(gof)(x) = x² + 2x + 1

Step-by-step explanation:

You can solve this by plugging  f into g and finding the result:

(gof)(x) = f(x)²

= (x + 1)²

= x² + 2x + 1

Answer: 5/2 because 2/5 times 4 is 8/2 plus 1/2 is 9/2

Step-by-step explanation:

Ani do niot know lol

Step-by-step explanation:

Answer:

J. 20ft

Step-by-step explanation:

1 2/3 = 5/3

5/3 * 12/1 = 60/3

60/3 = 20

Answer:

2983839i8

468393749493948

Hsjejrhrjjh4u4i84748394

Je83847483

373783838383884

373838383

Jkffffffffffffffffffffffffffffdddfddfffffffddddddddddddddddddfffffffffffffffffffffffffff

Answer:

The area of the fenced yard is 48 feet sq. and the perimeter is 32 feet.

Step-by-step explanation:

I hope this helps! Have a great rest of your day!

Answer:

435 in.²

Step-by-step explanation:

Surface area of the square pyramid = area of the square base + ½(Perimeter of base)(slant height)

Area of base = s²

s = 15 in

Area = 15² = 225 in²

Perimeter of the base = 4(15) = 60 in

Slant height = 7 in

Surface Area = 225 + ½(60)(7)

= 435 in.²

Answer:

it would be -11x^2+11x-4

Answer:

8y−56z+8

Step-by-step explanation:

Answer:

237.5

Step-by-step explanation:

2·(5·7.5+6.5·7.5+6.5·5)=237.5

Answer:

It should be 0.5 if I’m wrong let me know

Step-by-step explanation:

A=HbB/ 2 = 1x1/2=0.5