How do I work this problem out

How do you simplify this

Gala2k [10]

15 + 1 because you are using apsolute value so that negative 1 becomes a positive

8 0

3 years ago

What can you predict regarding the probability of the

natka813 [3]

Answer:

The frequency does not change with more trials

Step-by-step explanation:

To predict: the probability of the coin landing heads up

Solution:

Probability refers to the chances that an event will occur in an experiment. The value of probability lies between 0 and 1. 0 indicates impossible event and 1 indicates a sure event. The probability of an event can not be greater than 1.

When a coin is tossed, there are two possible outcomes: heads (H), tails (T).

In case of the probability of the coin landing heads up, the frequency does not change with more trials.

6 0

3 years ago

Read 2 more answers

Two major automobile manufacturers have produced compact cars with engines of the same size. We are interested in determining wh

Molodets [167]

Answer:

(A) The mean for the differences is 2.0.

(B) The test statistic is 1.617.

(C) At 90% confidence the null hypothesis should not be rejected.

Step-by-step explanation:

We are given that a random sample of eight cars from each manufacturer is selected, and eight drivers are selected to drive each automobile for a specified distance.

The following data (in miles per gallon) show the results of the test;

Driver Manufacturer A Manufacturer B

1 32 28

2 27 22

3 26 27

4 26 24

5 25 24

6 29 25

7 31 28

8 25 27

Let $\mu_1$ = mean MPG for the fuel efficiency of Manufacturer A brand

$\mu_2$ = mean MPG for the fuel efficiency of Manufacturer B brand

SO, Null Hypothesis, $H_0$ : $\mu_1-\mu_2=0$ or $\mu_1= \mu_2$ {means that there is a not any significant difference in the mean MPG (miles per gallon) when testing for the fuel efficiency of these two brands of automobiles}

Alternate Hypothesis, $H_A$ : $\mu_1-\mu_2\neq 0$ or $\mu_1\neq \mu_2$ {means that there is a significant difference in the mean MPG (miles per gallon) for the fuel efficiency of these two brands of automobiles}

The test statistics that will be used here is Two-sample t test statistics as we don't know about the population standard deviations;

T.S. = $\frac{(\bar X_1-\bar X_2)-(\mu_1-\mu_2)}{s_p\sqrt{\frac{1}{n_1}+\frac{1}{n_2} } }$ ~ $t__n__1+_n__2-2$

where, $\bar X_1$ = sample mean MPG for manufacturer A = $\frac{\sum X_A}{n_A}$ = 27.625

$\bar X_2$ = sample mean MPG for manufacturer B = $\frac{\sum X_B}{n_B}$ = 25.625

$s_1$ = sample standard deviation for manufacturer A = $\sqrt{\frac{\sum (X_A-\bar X_A)^{2} }{n_A-1} }$ = 2.72

$s_2$ = sample standard deviation manufacturer B = $\sqrt{\frac{\sum (X_B-\bar X_B)^{2} }{n_B-1} }$ = 2.20

$n_1$ = sample of cars selected from manufacturer A = 8

$n_2$ = sample of cars selected from manufacturer B = 8

Also, $s_p=\sqrt{\frac{(n_1-1)s_1^{2}+(n_2-1)s_2^{2} }{n_1+n_2-2} }$ = $\sqrt{\frac{(8-1)\times 2.72^{2}+(8-1)\times 2.20^{2} }{8+8-2} }$ = 2.474

(A) The mean for the differences is = 27.625 - 25.625 = 2

(B) The test statistics = $\frac{(27.625-25.625)-(0)}{2.474 \times \sqrt{\frac{1}{8}+\frac{1}{8} } }$ ~ $t_1_4$

= 1.617

(C) Now at 10% significance level, the t table gives critical values between -1.761 and 1.761 at 14 degree of freedom for two-tailed test. Since our test statistics lies within the range of critical values of t, so we have insufficient evidence to reject our null hypothesis as it will not fall in the rejection region due to which we fail to reject our null hypothesis.

Therefore, we conclude that there is a not any significant difference in the mean MPG (miles per gallon) when testing for the fuel efficiency of these two brands of automobiles.

5 0

4 years ago

Find the measure of arc DF (with an explanation of how to solve please!)

allochka39001 [22]

Answer:

mDF = 90°

(Assuming arc mCE is 5x + 10)

Step-by-step explanation:

When we have two chords crossing in a circle, there is a property where the angle in the cross point is equal half the sum of the corresponding arcs.

So in this case, we have:

70° = (mCE + mDF)/2

Assuming mCE is 5x + 10, we have:

70 = (5x + 10 + 11x + 2)/2

70 = (16x + 12)/2

70 = 8x + 6

8x = 64

x = 8

So the arc mDF is:

mDF = 11x + 2 = 11 * 8 + 2 = 90°

4 0

3 years ago

Which one is the right one? Help me please.

frez [133]

Answer:

90 km/h

Step-by-step explanation:

To solve this problem you first need to convert minutes to hours since the unit is km/h. Doing this we get half an hour (1 hour=60 mins so you divide 30 by 60) after converting you simply divide 45 by 1/2 or .5 to get the answer.

4 0

3 years ago