A sequence is defined by the following: an = 4n

What number sentence shows the commutative property of addition of 9+8=17

Ahat [919]

Given two numbers A and B, the commutative property of addition says:
A+B=B+A
Therefore:

9+8=8+9=17

5 0

4 years ago

1. A 2002 poll reported that 61% of people worried that they would be exposed to SARS.

Mama L [17]

Answer:

Part 1

a) $ME=1.96 \sqrt{\frac{0.61 (1-0.61)}{100}}=0.0956$

b) $ME=1.96 \sqrt{\frac{0.61 (1-0.61)}{363}}=0.0502$

c) $ME=1.96 \sqrt{\frac{0.61 (1-0.61)}{1551}}=0.0243$

Part 2

We can see that if we increase the sample size the margin of error decrease and that makes sense since n is on the denominator in the formula for the margin of error and if we increase the denominator the result needs to decrease.

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{p(1-p)}{n}})$

Part 1

For this case in order to find the margin of error we need to assume a confidence level fixed, let's assume 95% for example. The Margin of error is given by this formula:

$ME= z_{\alpha/2}\sqrt{\frac{p(1-p)}{n}}$

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 95% of confidence, our significance level would be given by $\alpha=1-0.95=0.05$ and $\alpha/2 =0.025$ . And the critical value would be given by:

$z_{\alpha/2}=-1.96, z_{1-\alpha/2}=1.96$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $\hat p = 0.61$ and we are interested in order to find the value of ME.

So we can replace for each case and see what we got:

a) $ME=1.96 \sqrt{\frac{0.61 (1-0.61)}{100}}=0.0956$

b) $ME=1.96 \sqrt{\frac{0.61 (1-0.61)}{363}}=0.0502$

c) $ME=1.96 \sqrt{\frac{0.61 (1-0.61)}{1551}}=0.0243$

Part 2

We can see that if we increase the sample size the margin of error decrease and that makes sense since n is on the denominator in the formula for the margin of error and if we increase the denominator the result needs to decrease.

7 0

4 years ago

One quart is approximately equal to 0.95 liter. To convert quarts to liters, which operation should you use?

Butoxors [25]

Answer:

the operation we use to convert quarts to liters : multiply

Step-by-step explanation:

One quart is approximately equal to 0.95 liter

Here quart is the larger unit and liter is the smaller unit

To convert larger unit to smaller unit we multiply

given that 1 quart = 0.95 liter

2 quart = 2 times 0.95

3 quart = 3 times 0.05

so to convert quart of liter we multiply

the operation we use to convert quarts to liters we multiply by 0.95

8 0

4 years ago

I NEED SOMEONE TO HELP ME WITH MATH RIGHT NOW

Liula [17]

Answer:

where is it

Step-by-step explanation:

3 0

3 years ago

A french class has a total of 25 student.The number of males is 7 more than the number of females how many males and how many fe

Lady_Fox [76]

Answer:

16 males and 9 females

Step-by-step explanation:

To solve this we can use a system of equations.

Let's start by naming the number of females x.

The number of males would then be y.

<u>Using these variables, we can set up 2 equations using info provided:</u>

A french class has a total of 25 students, -> x+y=25

The number of males is 7 more than the number of females -> x+7=y

Use substitution to solve.

<u>From the second equation:</u>

x+7=y

Subtract 7 from both sides.

x=y-7

Substitute that into the first equation.

x+y=25

y-7+y=25

Combine like terms.

2y-7=25

Add 7 to both sides.

2y=32

Divide both sides by 2.

y=16

Substitute y=16 into equation 2.

x+7=y

x+7=16

Subtract 7 from both sides.

x=9

Therefore, there are 16 males and 9 females in the french class.

3 0

3 years ago

Read 2 more answers

A sequence is defined by the following: an = 4n – 1 What is a1? What is a8?.