1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
kogti [31]
3 years ago
10

Which statements are true select each correct answer​

Mathematics
1 answer:
alexandr1967 [171]3 years ago
4 0
The first and the second one are true statements.
You might be interested in
How much of a spice that is 30% salt should be added to 175 ounces of a spice that is 65% salt in order to make a spice that is
klasskru [66]
\bf \begin{array}{lccclll}
&amount&concentration&
\begin{array}{llll}
concentrated\\
amount
\end{array}\\
&-----&-------&-------\\
\textit{30\% spice}&x&0.30&0.30x\\
\textit{65\% spice}&175&0.65&(175)(0.65)\\
-----&-----&-------&-------\\
mixture&x+175&0.50&(x+175)(0.50)
\end{array}

so.. as you can see, we use the decimal notation for the percentages... 65% is just 65/100 and 50% is just 50/100 and so on

so.. whatever the salted amounts are, we know they'll add up to (x+175)(0.50)

thus  (0.30x) + (175)(0.65) = (x+175)(0.50)

solve for "x"
5 0
3 years ago
A bag contains 5 back marbles 10 red marbles and 20 blue marble which statement is true
Galina-37 [17]
What are the statements?
4 0
2 years ago
The mean of a set of data is 148.87 and its standard deviation is 68.29. Find the z score for a value of 490.19.
Ksivusya [100]
<span>The mean of a set of data is 148.87 and its standard deviation is 68.29. Find the z score for a value of 490.19
the z-score is given by:
z=(x-</span>μ<span>)/</span>σ
plugging in the values in the expression we get:
z=(490.19-149.87)/68.29
z=340.32/68.29
z=4.9835
6 0
3 years ago
Jack can build 1/5 of a shed in the same time Kyle build 5/8 of a shed. How much of a shed will jack have built when Kyle has fi
nadya68 [22]

Answer:

Step-by-step explanation:

If Kyle can get 5/8 of a shed built in x amount of time, he can get 62.5% done; if Jack can get 1/5 of the shed built in the same time, he can 20% of it done. As a ratio:

\frac{Kyle}{Jack}:\frac{62.5}{20}  Kyle gets the whole thing done, 100% of the way, leaving Jack lagging behind at a somewhat lower percentage of the work being done.

\frac{Kyle}{Jack}:\frac{62.5}{20}=\frac{100}{x} and cross multiply to solve for the percentage of the shed built by Jack by the time Kyle gets it completed:

62.5x = 2000 so

x = 32%

4 0
3 years ago
With a height of 68 ​in, Nelson was the shortest president of a particular club in the past century. The club presidents of the
Ivahew [28]

Answer:

a. The positive difference between Nelson's height and the population mean is: \\ \lvert 68-70.7 \rvert = \lvert 70.7-68 \rvert\;in = 2.7\;in.

b. The difference found in part (a) is 1.174 standard deviations from the mean (without taking into account if the height is above or below the mean).

c. Nelson's z-score: \\ z = -1.1739 \approx -1.174 (Nelson's height is <em>below</em> the population's mean 1.174 standard deviations units).

d. Nelson's height is <em>usual</em> since \\ -2 < -1.174 < 2.

Step-by-step explanation:

The key concept to answer this question is the z-score. A <em>z-score</em> "tells us" the distance from the population's mean of a raw score in <em>standard deviation</em> units. A <em>positive value</em> for a z-score indicates that the raw score is <em>above</em> the population mean, whereas a <em>negative value</em> tells us that the raw score is <em>below</em> the population mean. The formula to obtain this <em>z-score</em> is as follows:

\\ z = \frac{x - \mu}{\sigma} [1]

Where

\\ z is the <em>z-score</em>.

\\ \mu is the <em>population mean</em>.

\\ \sigma is the <em>population standard deviation</em>.

From the question, we have that:

  • Nelson's height is 68 in. In this case, the raw score is 68 in \\ x = 68 in.
  • \\ \mu = 70.7in.
  • \\ \sigma = 2.3in.

With all this information, we are ready to answer the next questions:

a. What is the positive difference between Nelson​'s height and the​ mean?

The positive difference between Nelson's height and the population mean is (taking the absolute value for this difference):

\\ \lvert 68-70.7 \rvert = \lvert 70.7-68 \rvert\;in = 2.7\;in.

That is, <em>the positive difference is 2.7 in</em>.

b. How many standard deviations is that​ [the difference found in part​ (a)]?

To find how many <em>standard deviations</em> is that, we need to divide that difference by the <em>population standard deviation</em>. That is:

\\ \frac{2.7\;in}{2.3\;in} \approx 1.1739 \approx 1.174

In words, the difference found in part (a) is 1.174 <em>standard deviations</em> from the mean. Notice that we are not taking into account here if the raw score, <em>x,</em> is <em>below</em> or <em>above</em> the mean.

c. Convert Nelson​'s height to a z score.

Using formula [1], we have

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

\\ z = \frac{68\;in - 70.7\;in}{2.3\;in}

\\ z = \frac{-2.7\;in}{2.3\;in}

\\ z = -1.1739 \approx -1.174

This z-score "tells us" that Nelson's height is <em>1.174 standard deviations</em> <em>below</em> the population mean (notice the negative symbol in the above result), i.e., Nelson's height is <em>below</em> the mean for heights in the club presidents of the past century 1.174 standard deviations units.

d. If we consider​ "usual" heights to be those that convert to z scores between minus2 and​ 2, is Nelson​'s height usual or​ unusual?

Carefully looking at Nelson's height, we notice that it is between those z-scores, because:

\\ -2 < z_{Nelson} < 2

\\ -2 < -1.174 < 2

Then, Nelson's height is <em>usual</em> according to that statement.  

7 0
3 years ago
Other questions:
  • NEED HELP FAST PLEASE!
    6·2 answers
  • Alvin at 1/3 of a pizza for dinner and took 1/6 of it for lunch the next day . How much pizza does he have left
    10·2 answers
  • Measurements of the sodium content in samples of two brands of chocolate bar yield the following results (in grams):
    9·1 answer
  • A set of data has a normal distribution with a mean of 29 and a standard deviation of 4. Find the percent of data within each in
    9·1 answer
  • Please help me with 4 and 5
    10·1 answer
  • Plz help me with this box and whisker plot I’m confused plz make the whisker plot and answer these questions Can you make a box
    11·1 answer
  • What is the quotient of 43.8 and 12
    15·2 answers
  • Guys which one please
    15·1 answer
  • Evaluate the expression when x= -3 and y=3 <br>y-8x​
    10·2 answers
  • How many ways can you arrange 28
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!