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3 years ago

The sum of two numbers is 28. The first number, x, is three times the second number, y.

Mathematics

1 answer:

saveliy_v [14]3 years ago

8 0

Answer:

x=21

y= 7

Step-by-step explanation:

x+y = 28

x = 3y

Substitute the second equation into the first

3y+y = 28

4y = 28

Divide by 4

4y/4 = 28/4

y = 7

Now we need to find x

x = 3*y

x = 3*7

x = 21

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A professor thinks that the students in her statistics class this term are less creative than most students at this university.

choli [55]

Answer:

It is not enough evidence to reject null hypothesis. It is not enough evidence to say that mean score is not equal to 35.

Step-by-step explanation:

$\mu=35\\n=23\\\=x=33\\s=5\\\alpha=0.1$

1. Null and alternative hypothesis

$H_{0}:\mu=35\\H_{1}:\mu$

2. Significance level

$\alpha=0.1\\1-\alpha=0.99$

Freedom degrees is given by:

$v=n-1\\v=23-1=22$

For a sgnificance level of 0,01 and 22 freedom degrees, t-student distribution value is:

$t_{0.01;23}=-2. 5083$

3. Test statistic

$t=\frac{\=x-\mu}{\frac{s}{\sqrt{n} } }$

$t=\frac{33-35}{\frac{5}{\sqrt{23} } }$

$t=-1,918$

In this case, we have an one left tailed analysis, it means that null hypothesis is rejected if $t$

$-1.918>-2.5083$

Conclusion:

It is not enough evidence to reject null hypothesis. It is not enough evidence to say that mean score is not equal to 35.

3 0

3 years ago

Please Help me ASAP i need to turn it in, in like 10 min. Please answer the questions in the screenshot ill give u 20 points Tha

Delvig [45]

Answer:

for #1 its the 1st and 4th box

for # 2 it's 13.5 and 20.25

Step-by-step explanation:

1st box - 10 ÷ 5 = 2 and 25 ÷ 5 = 5

4th box - 10 x 2 = 20 and 25 x 2 = 50

you have to make sure that you do the same thing for both sides of the equation

6 x 2.25 = 13.5

9 x 2.25 = 20.25

Dilation is an enlarging or shrinking of a math figure using a specific scale factor

multiply your numbers by that given scale factor to give you your answer of option 2

hope this is right I'm not completely positive about the send one.

4 0

3 years ago

a rectangular table measures 48 inches wide and 60 inches long. a tablecloth covers the table and hangs over the edge by 10 inch

ololo11 [35]

5040
........................

8 0

3 years ago

PLEASE PLEASE HELP PLEASE

kogti [31]

Answer:

r = 6

Step-by-step explanation:

Using Pythagoras' identity in the right triangle

PR² = PQ² + QR² , substitute values

(r + 4)² = r² + 8²

r² + 8r + 16 = r² + 64 ( subtract r² from both sides )

8r + 16 = 64 ( subtract 16 from both sides )

8r = 48 ( divide both sides by 8 )

r = 6

3 0

3 years ago

Given the two functions, which statement is true?

tia_tia [17]

Answer:

Option D

Step-by-step explanation:

f(x) = $\text{log}_{15}x$

Transformed form of the function 'f' is 'g'.

g(x) = $\frac{1}{2}\text{log}_{15}(x+4)$

Property of vertical stretch or compression of a function,

k(x) = x

Transformed function → m(x) = kx

Here, k = scale factor

1). If k > 1, function is vertically stretched.

2). If 0 < k < 1, function is vertically compressed.

From the given functions, k = $\frac{1}{2}$

Since, k is between 0 and $\frac{1}{2}$ , function f(x) is vertically compressed by a scale factor $\frac{1}{2}$ .

g(x) = f(x + 4) represents a shift of function 'f' by 4 units left.

g(x) = f(x - 4) represents a shift of function 'f' by 4 units right.

g(x) = $\frac{1}{2}\text{log}_{15}(x+4)$

Therefore, function f(x) has been shifted by 4 units left to form image function g(x).

Option D is the answer.

8 0

3 years ago