2.Name the factors in each of the following problems.

The average gasoline price of one of the major oil companies in Europe has been $1.25 per liter. Recently, the company has under

Ann [662]

Answer:

$t=\frac{1.20-1.25}{\frac{0.14}{\sqrt{49}}}=-2.50$

Step-by-step explanation:

Data given and notation

$\bar X=1.20$ represent the sample mean given

$\sigma = 0.14$ represent the population standard deviation

$n=49$ sample size

$\mu_o =1.25$ represent the value that we want to test

t would represent the statistic (variable of interest)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the true mean for the gasoline prices is lower than 1.25, the system of hypothesis would be:

Null hypothesis: $\mu \geq 1.25$

Alternative hypothesis: $\mu < 1.25$

If we analyze the size for the sample is > 30 but we don't know the population deviation so is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

Calculate the statistic

We can replace in formula (1) the info given like this:

$t=\frac{1.20-1.25}{\frac{0.14}{\sqrt{49}}}=-2.50$

5 0

3 years ago

Which rational number represents a decrease in water level from 8 feet to 6 feet?

Alexxx [7]

-6/8...I guess so
Tell me if it is right or not

6 0

3 years ago

Devon made a box with length x+1, width x+3, and height x-3. What is the volume of Devon's box as a function of x?

erica [24]

Answer:

(a)

$V=x^3+x^2-9x-9$

(b)

$x=10$

(c)

$x=\frac{7}{2}$

Step-by-step explanation:

we are given

length is x+1

$L=x+1$

width is x+3

$W=x+3$

height is x-3

$H=x-3$

(a)

we can use volume formula

$V=L\times W\times H$

now, we can plug it

$V=(x+1)\times (x+3)\times (x-3)$

now, we can simplify it

$V=x^3+x^2-9x-9$

(b)

we are given volume =1001

so, we can set V=1001

and then we can solve for x

$V=x^3+x^2-9x-9=1001$

now, we can factor it

$\left(x-10\right)\left(x^2+11x+101\right)=0$

$x-10=0$

$x=10$

(b)

we are given volume

so, we can set

$V=14\frac{5}{8}=\frac{14\times 8+5}{8}$

$V=\frac{117}{8}$

and then we can solve for x

$V=x^3+x^2-9x-9=\frac{117}{8}$

now, we can factor it

$8x^3+8x^2-72x-189=0$

$\left(2x-7\right)\left(4x^2+18x+27\right)=0$

$2x-7=0$

$x=\frac{7}{2}$

8 0

3 years ago

8x + y = 20<br> x - 2y = -6

OleMash [197]

Answer: the answer is

Step-by-step explanation:

6 0

2 years ago

10. The sum of two numbers is 6 less than twice the first number. Their difference is 10 less than four times the second number.

Ilya [14]

Answer:

10 and 4.

Step-by-step explanation:

Let x be the first number.

Let y be the second number.

x + y = 2x - 6

x - y = 4y - 10

x = 4y - 10 + y

x = 5y - 10

(5y - 10) + y = 2(5y - 10) - 6

6y - 10 = 10y - 20 - 6

6y - 10 = 10y - 26

6y - 10y = -26 + 10

-4y = -16

y = 4

x - (4) = 4(4) - 10

x - 4 = 16 - 10

x - 4 = 6

x = 6 + 4

x = 10

3 0

3 years ago