B=36°, a =38, c=18

The highway department is testing two types of reflecting paint for concrete bridge end pillars. The two kinds of paint are alik

tankabanditka [31]

Answer:

a. difference of means

Step-by-step explanation:

Given that :

Mean , x = 9.4

Standard deviation, $s.d_1$ = 2.5

Number, $n_1$ = 12

Mean, y = 6.5

standard deviation, $s.d_2$ = 2.4

Number, $n_2$ = 12

The null hypothesis is : $H_0: \mu_1=\mu_2$

The alternate hypothesis is : $H_1: \mu_1>\mu_2$

Level of significance, $\alpha$ = 0.1

From the $\text{standard normal table, right tailed,}$ $t_{1/2}$ = 1.363

Since out test is right tailed.

Reject $H_0$ , if $T_0>1.363$

We use the test statics,

$t_0=\frac{(x-y)}{\sqrt{\frac{s.d_1}{n_1}+\frac{s.d_2}{n_2}}}$

$t_0=\frac{(9.4-6.5)}{\sqrt{\frac{6.25}{12}+\frac{5.76}{12}}}$

$t_0=2.899$

$|t_0|=2.899$

$\text{Critical value}$

The value of $|t_{1/2}|$ with minimum $\left(n_1-1,n_2-1)$ that is 11 df is 1.363

We go $|t_0|=2.899$ and $|t_{1/2}|$ = 1.363

Decision making:

Since the value of $|t_0|>|t_{1/2}|$$ and we reject the $H_0$

The p-value : right tail $H_a:(p>2.8988)$

= 0.00724

Therefore the value of $p_{0.1} > 0.00724$ , and so we reject the $H_0$

Thus we are testing 'the difference of means" in this problem.

7 0

3 years ago

Lindsey found the median and mean of the list of numbers below: 4, 6, 8, 8, 15 If the number 23 was added to the list, then ____

Sav [38]

D.) The mean will increase

The mean is all the numbers added together than divided by the amount of numbers there, so if you do this: 4 + 6 = 10 + 16 = 26 + 15 = 41/5 = 8.2

4 + 6 = 10 + 16 = 26 + 15 = 41 + 23 = 64/6 = 10.66666666666

As you can see it increased! Hope this helped! Pls give brainiest if you can

6 0

4 years ago

How would you find the volume of a tower created from 1,000 cans that were each 12oz in volume?

vlabodo [156]

Answer:

Multiply the number of cans by the volume of each: 12,000 oz.

Step-by-step explanation:

You find the total volume of more than one can by adding the volumes of the cans involved.

For 2 cans, the volume would be ...

12 oz + 12 oz = 24 oz

__

When you consider adding numbers more than a couple of times, you start looking for ways to simplify the effort. Multiplication was invented for that purpose. Here, multiplying the volume of 1 can by 1000 is the same as adding the volumes of 1000 cans.

For 1000 cans with volume of 12 oz each, the volume of the total is ...

1000 × 12 oz = 12,000 oz.

3 0

4 years ago

Please help thank u.

Sever21 [200]

Answer:

-4, 3 1/2 JFURE8EGNRODG RE NEJEUSUEHEUE I did this for 20 characters

4 0

3 years ago

In Still Water, Peters Boat Goes 4 Times as Fast as the Current of the River. He Took a Trip 15 Miles Up the River, Then Came Ba

inn [45]

Answer:

2 km/h

Step-by-step explanation:

Let

Rate of river current = x km/h

Speed of Peter's boat = 4x km/h

He takes 15 km trip up (opposite direction)

His speed upstream = 4x - x

= 3x

His speed is 3x and distance is 15 km

Time = Distance / Speed

15/3x

= 5/x

And

Moving downstream (same direction)

Speed will be 4x + x = 5x

Distance = 15km,

speed = 5x

Time = Distance / Speed

= 15/5x

= 3/x

Total time take for trip = 4 hours

Total time take for trip = upstream + downstream

4 =5/x + 3/x

4 = 8/x

Cross product

4 * x = 8

x = 8/4

x = 2

Rate of river current = x km/h

= 2 km/h

3 0

3 years ago