What is the answer to 12÷4+(25-6)

5. The superintendent of the local school district claims that the children in her district are brighter, on average, than the g

anygoal [31]

Answer:

We conclude that children in district are brighter, on average, than the general population.

Step-by-step explanation:

We are given the following data set:

105, 109, 115, 112, 124, 115, 103, 110, 125, 99

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.

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

$Mean =\displaystyle\frac{1117}{10} = 111.7$

Sum of squares of differences = 642.1

$S.D = \sqrt{\frac{642.1}{49}} = 8.44$

We are given the following in the question:

Population mean, μ = 106

Sample mean, $\bar{x}$ = 111.7

Sample size, n = 10

Alpha, α = 0.05

Sample standard deviation, s = 8.44

First, we design the null and the alternate hypothesis

$H_{0}: \mu = 106\\H_A: \mu > 106$

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

Formula:

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

Putting all the values, we have

$t_{stat} = \displaystyle\frac{111.7 - 106}{\frac{8.44}{\sqrt{10}} } = 2.135$

Now,

$t_{critical} \text{ at 0.05 level of significance, 9 degree of freedom } = 1.833$

Since,

$t_{stat} > t_{critical}$

We fail to accept the null hypothesis and reject it. We accept the alternate hypothesis.

We conclude that children in district are brighter, on average, than the general population.

4 0

3 years ago

School starts in 45 minutes and you live 17 miles from school. What average speed (in miles per hour) do you need to travel in o

Arada [10]

It would be 22.67mph

3 0

4 years ago

Help:) Factor f(x) = 4x^3+ 23x^2- 70x + 16 into linear factors given that - 8 is a zero of f(x).

Charra [1.4K]

Answer:

(x + 8)(x - 2)(4x - 1)

Step-by-step explanation:

Given that x = - 8 is a zero then (x + 8) is a factor

Divide f(x) by (x + 8) using Synthetic division

- 8 | 4 23 - 70 16

↓ - 32 72 - 16

---------------------------------

4 - 9 2 0

Quotient = 4x² - 9x + 2 = (x - 2)(4x - 1)

Thus

f(x) = (x + 8)(x - 2)(4x - 1)

8 0

3 years ago

there are 6 minutes of commercials for every 24 minutes of television how many minutes of commercials are there in one hour and

Nitella [24]

Answer:

Step-by-step explanation:

1 hour and 36 minutes = 60 minutes + 36 minutes = 96 minutes

6/24 = x/96

24x = 6 * 96

24x = 6 * 4 * 24

x = 24

3 0

3 years ago

4 divided 1/5 hep me plz

bulgar [2K]

Answer:

4/1/5=20 because when you divide by a fraction u keep change the divison into multiplaicton and flip the 1/5 to 5/1 so 4x5

Step-by-step explanation:

4 0

3 years ago