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3 years ago

Practice test

Mathematics

2 answers:

Elan Coil [88]3 years ago

7 0

Answer:

Step-by-step explanation:

mariarad [96]3 years ago

3 0

Answer:

it's a rectangle so the area is 6×8=48

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Parker is designing a new board game, and is trying to figure out all the possible outcomes. How many different possible outcome

lutik1710 [3]

Answer:60

Step-by-step explanation:

4*3*5

7 0

3 years ago

I) Construct a triangle PQR such that |PQ|=8cm,{RPQ=90°{PQR=30°.Measure |RQ|

scoray [572]

Answer:

6.93 cm

Step-by-step explanation:

You have a right triangle (90°), so you do as follow:

If I understand correctly, you are looking for the hypotenuse so

$cos(30) = \frac{PQ}{QR} = \frac{8 cm}{QR}$

That is equal to $QR = cos(30)*8 cm = 6.928 cm$

5 0

3 years ago

((60 points to whoever answers all of these))

Readme [11.4K]

1. 9^2

2. 15^3

3. 14^3

4. 11^5

5. 16^4

3 0

3 years ago

Read 2 more answers

Suppose that the mean water hardness of lakes in Kansas is 425 mg/L and these values tend to follow a normal distribution. A lim

tino4ka555 [31]

Answer:

The mean water hardness of lakes in Kansas is 425 mg/L or greater.

Step-by-step explanation:

We are given the following data set:

346, 496, 352, 378, 315, 420, 485, 446, 479, 422, 494, 289, 436, 516, 615, 491, 360, 385, 500, 558, 381, 303, 434, 562, 496

Formula:

$\text{Standard Deviation} = \sqrt{\displaystyle\frac{\sum (x_i -\bar{x})^2}{n-1}}$

where $x_i$ are data points, $\bar{x}$ is the mean and n is the number of observations.

$Mean = \displaystyle\frac{\text{Sum of all observations}}{\text{Total number of observation}}$

$Mean =\displaystyle\frac{10959}{25} =438.36$

Sum of squares of differences = 175413.76

$S.D = \sqrt{\dfrac{175413.76}{24}} = 85.49$

Population mean, μ = 425 mg/L

Sample mean, $\bar{x}$ = 438.36

Sample size, n = 25

Alpha, α = 0.05

Sample standard deviation, s = 85.49

First, we design the null and the alternate hypothesis

$H_{0}: \mu \geq 425\text{ mg per Litre}\\H_A: \mu < 425\text{ mg per Litre}$

We use one-tailed t test to perform this hypothesis.

Formula:

$t_{stat} = \displaystyle\frac{\bar{x} - \mu}{\frac{s}{\sqrt{n}} }$

Putting all the values, we have

$t_{stat} = \displaystyle\frac{438.36 - 425}{\frac{85.49}{\sqrt{25}} } = 0.7813$

Now, $t_{critical} \text{ at 0.05 level of significance, 24 degree of freedom } = -1.7108$

Since,

The calculated t-statistic is greater than the critical value, we fail to reject the null hypothesis and accept it.

Thus, the mean water hardness of lakes in Kansas is 425 mg/L or greater.

6 0

3 years ago

Help please :) will give brainlist

Savatey [412]

Answer:

34.9

Step-by-step explanation:

Because if you multiply then divide by 2 that will help you alot.

8 0

3 years ago