Question

Please I need help! I am only 12 so please dont be mean.
At West Middle School, 30% of students have a dog, 20% of students have a cat, 10% of students have another kind of pet, and 40% of students have no pets.

a) Explain how you can use a random-number table to find the experimental probability that in a group of 5 students, at least 2 will have a dog.

b) Use your model from part a and the table below to find the experimental probability that in a group of 5 students, at least 2 will have a dog.

Answer 1

@stuckinarut
> I am only 12 so please dont be mean.

If anybody is mean to you on OpenStudy, click on the "report abuse" underneath the rectangle in which the mean person wrote. Write: I'm 12 and this person was mean to me." A Mod will investigate.

Answer 2

Thank you very much I dont want answer just given to me I just need some help and people can be really mean so thank you for your help

Answer 3

This table you uploaded - is it a portion of a random number table?

Answer 4

thats all it gave me with the questions above it and i dont understand the table at all

Answer 5

@Directrix you shouldn't do that, because you have to be at least 13 to use Open Study

Answer 6

my mom is with me so we didnt think this would be a problem as it is signed in under my older brothers account who is 16

Answer 7

Oh, then it is fine :) and if anything wrong occurs, don't hesitate to tell a moderator!!!

Answer 8

ok thanks

Answer 9

Back to the question, are the numbers you uploaded numbers from a *random number table* or are those numbers related to the number of dogs, cats, and pets in the stated problem.

I understand that you don't understand the random number table part but look at the given question in your text or wherever and be sure that you have posted all the information.

Answer 10

This is the whole problem

Answer 11

Explain how you can use a random-number table to find the experimental probability that in a group of 5 students, at least 2 will have a dog.
-------------------------

30% of students have a dog,
20% of students have a cat,
10% of students have another kind of pet,
40% of students have no pets.
------------
The percentages account for 100% or all of the students.
--------------

The random number table is set up in groups of 5 digits.
The five digits are like a group of 5 random students from
West Middle School.

Say, in the first five digits of the table for this problem, the digits 6 5 9 2 6 appear.
Those digits are like people with the particular digit showing that the person does or does not have a dog.

Before using the table, the digits zero through 9 have to be assigned so that they reflect the percentage of students who have dogs.

30% have a dog.

30% = 30 * 1/100 = 3/10.

Assign digits 0, 1, and 2 to mean that a student has a dog.

Digits 3 through 9 mean that a student does not have a dog.

Digits 0, 1, and 2 are one-third the number of digits 3, 4, 5, 6, 7, 8, and 9.
So, the the 3/10 = 30% of the students have dogs is preserved by the assignment of digits for dogs and non-dogs.

Note: You could use digits 7, 8, and 9 to represent "has a dog" and the other 7 as "has no dog." What is important is not the digits assigned but that 3 of the ten digits mean "has a dog." That is important because it is what is given and we are empirically (by simulation) checking out that 30% of the students at WMS have a dog.

Answer 12

Back to the random number table.

Looking at the first five digits,

6 5 9 2 6 --> I will think of this as 5 people to whom I am asking, "Do you have a dog?"
The first person-digit is a "6." That is a reply of NO dog.
The second person "says" 5. That is a reply of NO dog.
The third person says 9. That is a reply of NO dog.
The fourth person says "2." That is a reply of YES dog.
The fifth person says "6." That is a reply of NO dog.

For Group One, of the 5 people, one has a dog.

On a tally sheet, this result will be shown as:
Group One -------- 1 dog

Repeat this 19 times for a total of 20 groups of 5 people.
At the end of the 20th group, add the total number of dogs for all 20 groups.
Divide that sum by 20 which is the number of groups surveyed.

That answer will be the experimental probability of that in a group of 5, at least 2 will have a dog.

That is how the table will be used to find the experimental probability that in a group of 5, at least 2 will have a dog.

Answer 13

Part b)

Second Group of 5 people, Column One of the table (you can go across by rows if you like - the digits are random so it does not matter)

2 7 3 8 7

2 Dog

7 No

3 No

8 No

7 No

For Group Two, one dog. Enter that on the tally sheet (see below).

Answer 14

This is experimental probability. You are not expected to get an answer of 3 dogs after you do the 20 trials (groups).

If you conduct 100 or 1000 trials (rather than 20), you will likely get a better estimate of the actual number of dogs per five people, but there is no guarantee.

If you change the digit assignments so that 7, 8, and 9 represent dogs, you may alter the final experimental probability a bit but the answer will be no "truer" than the one obtained using the digit assignment above. Three digits out of 10 is 30% regardless of which digits are chosen as "dogs."

So, other students in your class may get a slightly different answer than you. That is to be expected unless they used the same dog digit assignment as you.

Have fun with this.

@stuckinarut

Answer 15

@stuckinarut You may want to delete the two files you uploaded.(graph4.png and problem.png) They are no longer needed.

Answer 16

Wow cool thank you very much this helped alot

Answer 17

Okay. I'll check back later to see if you have any questions.