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3 years ago

A number is randomly picked from this list: 10, 20, 30, 40, 50. what is the probability of picking an even number

1 answer:

7 0

Hey there! :)

There are 5 numbers.

Even numbers end with 2, 4, 6, 8, or 0

All of the numbers end in 0

That means all the numbers are even

Your answer is: 5/5 = 1

Hope this helps :)

You might be interested in

A sample of 25 undergraduates reported the following dollar amounts of entertainment expenses last year:

Kaylis [27]

Answer:

mean = 724.2

Median = 715

Mode = 768

Range = 85

Standard deviation = 29.30

Interval = [665.6, 782.8]

Step-by-step explanation:

Number of samples n = 25

Summation X= 769 + 691 + 699 +730+711+ 765+ 702 718 +719 +712+ 768 +688 +757+695 768 +735 +709 +758 +708+ 693 +736 700+ 687 +772 +715 = 18105

1. Mean = 18105/25

= 724.2

2. Median is the middle value when arranged from the least value to the highest = 715

3. Mode is the number with the highest frequency = 768 (occured two times)

1. Range = highest value - lowest value

Highest value = 772

Lowest value = 687

772-687 = 85

2. Standard deviation = √(X-barX)²/n-1

= √20604/25-1

=√858.5

= 29.30

Please check attachment for the full calculation of the standard deviation

Interval

[Mean - 2(sd), mean + 2(sd)]

= [724.2-2x29.3, 724.2+2x29.3]

=[665.6, 782.8]

4 0

2 years ago

Lewis is rolling a 10-sided die 250 times. Each side of the die is labeled with a number 1 – 10. Based on the theoretical probab

oksano4ka [1.4K]

75 time because the proabablity of rolling any number each time is 1/10 so 250/10=25 the mutiples of 3 in 1-10 are 3,6,9 so 3*25 =75 tmes

5 0

2 years ago

Read 2 more answers

Solve for x 9(x-1) = 2

Katen [24]

Answer: x = 9/11

Step-by-step explanation:

First, distribute 9 to x and -1

9x - 9 = 2

Then add 9 to both sides

9x = 11

Then divide both sides by 9

x = 9/11

Hope it helps :)

4 0

2 years ago

Dinosaur fossils are often dated by using an element other than carbon, like potassium-40, that has a longer half life (in this

Firlakuza [10]

The amount of substance left of a radioactive element of half life, $t_{\frac{1}{2}}$ after a time, t, is given by:

$N(t)=N_0\left( \frac{1}{2} \right)^ \frac{t}{t_{ \frac{1}{2} }}$

Given that <span>potassium-40 has a half life of approximately 1.25 billion years.

The number of years it will take for 0.1% of potassium-40 to remain is obtained as follows:

$0.1=100\left( \frac{1}{2} \right)^ \frac{t}{1.25}} \\ \\ \Rightarrow\left( \frac{1}{2} \right)^ \frac{t}{1.25}}=0.001 \\ \\ \Rightarrow\frac{t}{1.25}\ln\left( \frac{1}{2} \right)=\ln(0.001) \\ \\ \Rightarrow \frac{t}{1.25}= \frac{\ln(0.001)}{\ln\left( \frac{1}{2} \right)} =9.966 \\ \\ t=9.966(1.25)=12.5$

Therefore, </span><span>the maximum age of a fossil that we could date using 40k is 12.5 billion years.</span>

3 0

3 years ago

The mayor of a town has proposed a plan for the construction of an adjoining bridge. A political study took a sample of 13001300

Ket [755]

Answer:

No, there is not enough evidence at the 0.02 level to support the strategist's claim.

Step-by-step explanation:

We are given that a political study took a sample of 1300 voters in the town and found that 57% of the residents favored construction.

And, a political strategist wants to test the claim that the percentage of residents who favor construction is more than 54%, i.e;

Null Hypothesis, $H_0$ : p = 0.54 {means that the percentage of residents who favor construction is 54%}

Alternate Hypothesis, $H_1$ : p > 0.54 {means that the percentage of residents who favor construction is more than 54%}

The test statistics we will use here is;

T.S. = $\frac{\hat p -p}{\sqrt{\frac{\hat p(1- \hat p)}{n} } }$ ~ N(0,1)

where, p = actual percentage of residents who favor construction = 0.54

$\hat p$ = percentage of residents who favor construction in a sample of

1300 voters = 0.57

n = sample of voters = 1300

So, Test statistics = $\frac{0.57 -0.54}{\sqrt{\frac{0.57(1- 0.57)}{1300} } }$

= 2.185

Now, at 0.02 significance level, the z table gives critical value of -2.3263 to 2.3263. Since our test statistics lie in the range of critical values which means it doesn't lie in the rejection region, so we have insufficient evidence to reject null hypothesis.

Therefore, we conclude that the percentage of residents who favor construction is 54% and the strategist's claim is not supported.

4 0

3 years ago