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2 years ago

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Suppose a distribution has a mean of 40, and a standard deviation of 5, if 3 is added to each value in the data what is the new

mean and standard divination?

1 answer:

Kamila [148]2 years ago

5 0

Answer:

Step-by-step explanation:

the mean would be 40+3= 43

the standard deviation wouldn't change

mean= 43

standard deviation= 5

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Find the volume of the prism.

anygoal [31]

the answer is d i think

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3 years ago

New Clarendon Park is undergoing renovations to its gardens. One garden that was originally a square is being adjusted so that o

frosja888 [35]

The answer is 80 square meters.

The square area is expressed as:
A = a²,
where A is the area of the square, and a is the side of the square.

The rectangle area is expressed as:
A₁ = a₁ · b₁,
where A₁ is the area of the rectangle, and a₁ and b₁ are the sides of the rectangle.

After renovations, square garden becomes rectangular.

One side is doubled in length:
a₁ = 2a

The other side is decreased by three meters.
b₁ = a - 3

The new area is 25% than the original square garden:
A₁ = A + 25%A =
= A + 25/100·A
= A + 1/25·A
= a² + 1/25·a²
= <span>a² + 0.25·a²
</span> = 1.25·a²

If the starting equation is:
A₁ = a₁ · b₁

Thus, the equation is:
1.25a² = 2a·(<span>a - 3)
</span>1.25a² = 2a · a - 2a · 3
1.25a² = 2a² - 6a

<span>Therefore, the equation that could be used to determine the length of a side of the original square garden is:
</span><u>2a² - 6a = </u><span><u>1.25a²</u></span>

Now, we will solve the equation:
2a² - 6a = 1.25a²
2a² - 1.25a² - 6a = 0
0.75a² - 6a = 0
⇒ a(0.75a - 6) = 0

From here, one of the multiplier must be zero - either a or (0.75a - 6). Since a could not be zero, (0.75a - 6) is:
0.75a - 6 = 0
0.75a = 6
a = 6 ÷ 0.75
a = 8

If the side of the square is 8, then the area of the rectangle is
A₁ = 1.25 · a²
A₁ = 1.25 ·8²
A₁ = 1.25 · 64
A₁ = 80

Therefore, the area of the new rectangle garden is 80 square meters.

4 0

4 years ago

Is C=pi d partial variation or direct or neither

Marizza181 [45]

This is a direct variation

C = pi*d

pi is a constant and it does thru (0,0)

3 0

3 years ago

A recent national survey found that high school students watched an average (mean) of 7.2 movies per month with a population sta

VladimirAG [237]

Answer:

1. Option A

2. Option D) Reject null hypothesis if z < –1.645

3. z = -4.90

4. P-value = 0.00001

Step-by-step explanation:

We are given the following in the question:

Population mean, μ = 7.2

Sample mean, $\bar{x}$ = 6.5

Sample size, n = 49

Alpha, α = 0.05

Population standard deviation, σ = 1.0

a) First, we design the null and the alternate hypothesis

$H_{0}: \mu \geq 7.2\text{ movies per month}\\H_A: \mu < 7.2\text{ movies per month}$

Option A) is the correct answer

We use one-tailed(left) z test to perform this hypothesis.

c) Formula:

$z_{stat} = \displaystyle\frac{\bar{x} - \mu}{\frac{\sigma}{\sqrt{n}} }$

Putting all the values, we have

$z_{stat} = \displaystyle\frac{6.5 - 7.2}{\frac{1}{\sqrt{49}} } = -4.90$

b) Now, $z_{critical} \text{ at 0.05 level of significance } = -1.645$

Rejection rule:

If calculated z-statistic is less than the critical z-value, we reject the null hypothesis.

Option D) Reject null hypothesis if z < –1.645

d) Now, we calculate the p-value with the help of standard normal table.

P-value = 0.00001

Since the p-value is lower than the significance level, we fail to accept the null hypothesis and reject it.We accept the alternate hypothesis.

We conclude that the college students watch fewer movies a month than high school students.

6 0

3 years ago

Largest to smallest 4 3/5 -17 3/5 -14 5/5

Stolb23 [73]

Answer:

4 3/5, -14 5/5, -17 3/5

Step-by-step explanation:

7 0

3 years ago