Determine la razón de la siguiente progresión geométrica: 81,27,9,3,1,....

Find the simplified form of the expression. Given your answer in scientific notation (8 x 10^4)(9 x 10^8)

Lady bird [3.3K]

$(8 \times {10}^{4} )(9 \times {10}^{8} ) \\ = 8 \times 9 \times {10}^{4} \times {10}^{8 } \\ = 72 \times {10}^{4 + 8} \\ = 7.2 \times 10 \times {10}^{12} \\ = 7.2 \times {10}^{13}$

This is the answer with step by step explanation

6 0

3 years ago

Which point of intersection is the solution to the equations y = 2/5x-1/2 and y = -1/3x + 2/3?

abruzzese [7]

The answer is B because it is the only one where the line intersects on the y - axis at -1/2 and 2/3, which are the y -intercepts

7 0

3 years ago

A recipe for a cake needs 2 1/4 cups of cake. You are making 1/2 of the recipe. How many cups of flour do you need?

vazorg [7]

Answer:

4.5 or 1 1/8

Step-by-step explanation:

2 1/4 is a full box to back 1/2 of the flour you need to divide 2 1/4 in half

Half of 2 is 1 & half of 1/4 is 1/8

3 0

4 years ago

Read 2 more answers

Spring stretches by 21.0 cm when a 135 n object is attached. what is the weight of a fish that would stretch the spring by 62.1

Marta_Voda [28]

Caution: you need to use the same units of measurement throughout. If the spring stretches by 21 cm when a 135 newton object is attached, then you must ask for the mass (in newtons) of a fish that would stretch the spring by 62.1 cm.

We will need to assume that the spring is not stretched at all if and when no object is attached to the spring.

Write the ratio

21.0 cm 135 newtons
------------- = --------------------
62.1 cm x

Solve this for x. This x value represents the mass of a fish that would stretch the spring by 62.1 cm. You can cancel "cm" in the equation above:

21.0 135 newtons
------ = --------------------
62.1 x

Then 21.0x = (62.1)(135 newtons). Divide both sides of this equation by 21.0 to solve it for x.

7 0

3 years ago

Read 2 more answers

A recent study at UGA (March 5, 2008) suggests that students with cell phones may take more risks than students that do not have

Ira Lisetskai [31]

Answer:

(a) -2.8

b) (1) Reject H0: p = 0.50 in favor of HA: p < 0.50; there is sufficient evidence to conclude that less than half of all UGA female students who, if they had a cell phone, would be willing to walk somewhere after dark that they would normally not go.

Step-by-step explanation:

The test statistic is:

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

In which X is the sample mean, $\mu$ is the value tested at the null hypothesis, $\sigma$ is the standard deviation and n is the size of the sample.

H0: p = 0.50

This means that:

$\mu = 0.5, \sigma = \sqrt{0.5*0.5} = 0.5$

In a random sample of 305 UGA female students, 128 responded that, if they had a cell phone, they would be willing to walk somewhere after dark that they would normally not go.

This means that $n = 305, X = \frac{128}{305} = 0.4197$

a) Value of the test statistic:

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

$z = \frac{0.4197 - 0.5}{\frac{0.5}{\sqrt{305}}}$

$z = -2.8$

Pvalue:

We are testing the hypothesis that the proportion is less than 0.5, which means that the pvalue of the test is the pvalue of z = -2.81.

Looking at the z-table, z = -2.8 has a pvalue of 0.0026

(b) What is the correct conclusion for this hypothesis test at the 0.05 level of significance?

0.0026 < 0.05, which means that we reject the null hypothesis, that the proportion is 0.5, and accept the alternate hypothesis, that the proportion is less than 0.5, option (1).

6 0

3 years ago