All categories

3 years ago

I need help!!! Brainliest for first (correct) answer!

Mathematics

1 answer:

VMariaS [17]3 years ago

3 0

To do this without a calculator, I would change: 5.2 × 10^(-2) to ... 52×10^(-3)

--> then multiply the whole numbers 52 × 8 = 416

--> next add the exponents on the tens. -3 + -4 = -7

= 416×10^(-7)

* now they'll want you to move the decimal back to behind the first digit. (just standard convention)

= 4.16×10^(-5)

If you have a calculator you can just use the "EE" button for ×10^power typed in it looks like this :

5.2 EE -2 × 8 EE -4 =

then make sure your calculator is in scientific mode, otherwise you'll be counting decimal spaces

You might be interested in

The following 5 questions are based on this information: An economist claims that average weekly food expenditure of households

liq [111]

Answer:

Null hypothesis: $\mu_{1}-\mu_{0}\leq 0$

Alternative hypothesis: $\mu_{1}-\mu_{2}>0$

$SE=\sqrt{\frac{12.5^2}{35}+\frac{9.25^2}{30}}=2.705$

b) 2.70

$t=\frac{(164-159)-0}{\sqrt{\frac{12.5^2}{35}+\frac{9.25^2}{30}}}=1.850$

b. 1.85

$p_v =P(Z>1.85)=0.032$

b. 0.03

a. We can reject H(0) in favor of H(a)

Step-by-step explanation:

Data given and notation

$\bar X_{1}=164$ represent the mean for the sample 1

$\bar X_{2}=159$ represent the mean for the sample 2

$\sigma_{1}=12.5$ represent the population standard deviation for the sample 1

$s_{2}=9.25$ represent the population standard deviation for the sample B2

$n_{1}=35$ sample size selected 1

$n_{2}=30$ sample size selected 2

$\alpha=0.05$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the expenditure of households in City 1 is more than that of households in City 2, the system of hypothesis would be:

Null hypothesis: $\mu_{1}-\mu_{0}\leq 0$

Alternative hypothesis: $\mu_{1}-\mu_{2}>0$

We know the population deviations, so for this case is better apply a z test to compare means, and the statistic is given by:

$z=\frac{(\bar X_{1}-\bar X_{2})-0}{\sqrt{\frac{\sigma^2_{1}}{n_{1}}+\frac{\sigma^2_{2}}{n_{2}}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other".

Standard error

The standard error on this case is given by:

$SE=\sqrt{\frac{s^2_{1}}{n_{1}}+\frac{s^2_{2}}{n_{2}}}$

Replacing the values that we have we got:

$SE=\sqrt{\frac{12.5^2}{35}+\frac{9.25^2}{30}}=2.705$

b. 2.70

Calculate the statistic

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

$t=\frac{(164-159)-0}{\sqrt{\frac{12.5^2}{35}+\frac{9.25^2}{30}}}=1.850$

P-value

Since is a one side right tailed test the p value would be:

$p_v =P(Z>1.85)=0.032$

b. 0.03

Conclusion

If we compare the p value and the significance level given $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis.

a. We can reject H(0) in favor of H(a)

4 0

3 years ago

Approximate √12 to the nearest tenth.

Serjik [45]

Answer:

√12 in nearest tenth is 3.5 is the answer

7 0

2 years ago

Read 2 more answers

Please help!!

Marysya12 [62]

The LCD of 3 and 4 is 12. To make 4 into 12, we multiply it by three, so 3 would also have to be multiply by 3, turning 3/4 into 9/12.

The same thing applies to 1/3, only it needs to be multiplied by 4. So it would become 4/12

9/12 - 4/12 = 5/12

4 0

3 years ago

Read 2 more answers

Destin walked 2km and Jane walked 4,000 ft. What is the approximate combined distance they walked? Note: 1 Foot (ft) is equal to

Anna11 [10]

Answer: Option C.

Step-by-step explanation:

The data is:

Destin walked 2km

Jane walked 4000ft.

Let's write both of those in the same units.

The data given is:

1ft = 0.0003048km.

and 4000ft is 4000 times that:

4000ft = 4000*1ft = 4000*0.0003048km = 1.22km

Then if we add those, we get:

Total distance = 2km + 1.22km = 3.22km

So we can already discard option D.

Now, we know that:

1km = 0.6214 miles.

then 3.22 km is 3.22 times that amount:

3.22km = 3.22*1km = 3.22*(0.6214 mi) = 2 miles

The correct option is C.

3 0

3 years ago

Please help I have tried over and over and can't get it

nirvana33 [79]

1) -3
2) 6
3) 4
4) 2
5) 5
6) 5
7) 7
8) -3
9) 9
10) 6
11) -5
12) 0

Here are your answers may I please have the brainliest

5 0

2 years ago