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2 years ago

How many students studied more than 20 minutes

Mathematics

2 answers:

Crank2 years ago

7 0

9 students.
4 studied 21 minutes,
2 studies 22 minutes,
1 studied 23 minutes,
and 2 studied 30 minutes.
Hope this helps you:)

kiruha [24]2 years ago

5 0

9 students studied more than 20 minutes. Can I have brainliest, please?
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Hi can someone please help with this. I will reward

Lunna [17]

Answer:

it looks like its all right to me

Step-by-step explanation:

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2 years ago

Emily thinks the perfect tomato sauce has 8 cloves of garlic in every 500{ mL} of sauce. Raphael's tomato sauce has 12 cloves of

igomit [66]

For perfect solution we need to have :- 8 colves in 500ml solution

500 ml has 8 cloves

1 ml has 8 / 500 cloves

100ml has 8 / 500 * 100 = 8/5 = 1.6 cloves

Raphael's mixture

900 ml has 12 cloves

1 ml has 12 / 900 cloves

100 ml has 12 / 900 * 100 = 12 / 9 = 1.33 cloves

so concentration of garlic in 100 ml solution of Raphael's solution is less than Emily's solution so it is not garlicky enough. ( option B)

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2 years ago

Read 2 more answers

Which value, when placed in the circle, would result in a system of equations with infinitely many solutions?

Arlecino [84]

Answer:

A. -10

Step-by-step explanation:

I think you would do like this:

y=2x-5

what about 2y(2x-5) times 2)

so 2y=4x- (-10)

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2 years ago

This is really important i have to get this one tomorrow please help me

Murrr4er [49]

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2 years ago

In Applied Life Data Analysis (Wiley, 1982), Wayne Nelson presents the breakdown time of an insulating fluid between electrodes

ale4655 [162]

Answer:

The sample mean is $\bar{x}=14.371$ min.

The sample standard deviation is $\sigma = 18.889$ min.

Step-by-step explanation:

We have the following data set:

$\begin{array}{cccccccc}0.15&0.82&0.81&1.44&2.70&3.28&4.00&4.70\\4.96&6.49&7.25&8.03&8.40&12.15&31.89&32.47\\33.79&36.80&72.92&&&&&\end{array}$

The mean of a data set is commonly known as the average. You find the mean by taking the sum of all the data values and dividing that sum by the total number of data values.

The formula for the mean of a sample is

$\bar{x} = \frac{{\sum}x}{n}$

where, $n$ is the number of values in the data set.

$\bar{x}=\frac{0.15+0.82+0.81+1.44+2.7+3.28+4+4.7+4.96+6.49+7.25+8.03+8.4+12.15+31.89+32.47+33.79+36.80+72.92}{19}\\\\\bar{x}=14.371$

The standard deviation measures how close the set of data is to the mean value of the data set. If data set have high standard deviation than the values are spread out very much. If data set have small standard deviation the data points are very close to the mean.

To find standard deviation we use the following formula

$\sigma = \sqrt{ \frac{ \sum{\left(x_i - \overline{x}\right)^2 }}{n-1} }$

The mean of a sample is $\bar{x}=14.371$ .

Create the below table.

Find the sum of numbers in the last column to get.

$\sum{\left(x_i - \overline{X}\right)^2} = 6422.0982$

$\sigma = \sqrt{ \frac{ \sum{\left(x_i - \overline{x}\right)^2 }}{n-1} } = \sqrt{ \frac{ 6422.0982 }{ 19 - 1} } \approx 18.889$

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2 years ago