When we have a graph, and we look at the different frequencies of each class, then....

[urimagic]

I trust all is well with you...I'm going over some statistical questions with answers, and stumbled upon something that I just do not get, and cannot for the life of me find anything on the net that covers this ....thing...

When we have a graph, and we look at the different frequencies of each class, then the model class is obviously the range that has the higher frequency...

Sometimes we have [imath]4 \leq x < 10[/imath] and other times [imath]4 < x \leq 10[/imath]

How do I establish where the "equals" sign will be?

 

[khansaheb]

I trust all is well with you...I'm going over some statistical questions with answers, and stumbled upon something that I just do not get, and cannot for the life of me find anything on the net that covers this ....thing...

When we have a graph, and we look at the different frequencies of each class, then the model class is obviously the range that has the higher frequency...View attachment 35742

What is 'x'? Please define your variables?

In the first case 'x' CAN BE = 4 but CANNOT be = 10 ................... 'x' can take any value less than 10 (slightly less than 10 say 9.999999 but not 10) - down to equal to 4

In the second case 'x' CANNOT BE = 4 but CAN be = 10 ..... 'x' can take any value upto equal 10, BUT down to 4 (say 4.000000001 )- yet slightly more than 4.

 

[NotJeffM]

We are forced to guess what your question even means.

I am guessing that “model” actually means “modal.”

I am also guessing that the underlying data has been summarized into numerical ranges for a histogram or bar chart and that you do not have the underlying data.

I cannot even make an informed guess as to whether the raw data comes from a distribution that is continuous in principle or is discrete.

Nor can we even guess what you are trying to do when x is undefined. Actually, I suspect that you are using x in more than one sense, first as a proxy for the definition of the ranges (plural) and second as a single number standing for the mode, but that is mere suspicion.

In short, you must be much more specific to pose an answerable question. The question may be clear in your mind, but you must make it clear to our minds.

 

[urimagic]

What is 'x'? Please define your variables?

In the first case 'x' CAN BE = 4 but CANNOT be = 10 ................... 'x' can take any value less than 10 (slightly less than 10 say 9.999999 but not 10) - down to equal to 4

In the second case 'x' CANNOT BE = 4 but CAN be = 10 ..... 'x' can take any value upto equal 10, BUT down to 4 (say 4.000000001 )- yet slightly more than 4.

Ok, I'm sorry, I assumed using phrases like model class, it would suffice, okay, I was wrong...please forgive me...attached the actual question..We must write down the model class.
The answer is:

Why greater than 20, but smaller AND equal to 25?

 

[urimagic]

We are forced to guess what your question even means.

I am guessing that “model” actually means “modal.”

I am also guessing that the underlying data has been summarized into numerical ranges for a histogram or bar chart and that you do not have the underlying data.

I cannot even make an informed guess as to whether the raw data comes from a distribution that is continuous in principle or is discrete.

Nor can we even guess what you are trying to do when x is undefined. Actually, I suspect that you are using x in more than one sense, first as a proxy for the definition of the ranges (plural) and second as a single number standing for the mode, but that is mere suspicion.

In short, you must be much more specific to pose an answerable question. The question may be clear in your mind, but you must make it clear to our minds.

Hi, I have responded to someone else's post, if you don't mind looking at it for me?....Thank you kindly

 

[BigBeachBanana]

What is the actual question asking you to do?

 

[Dr.Peterson]

Ok, I'm sorry, I assumed using phrases like model class, it would suffice, okay, I was wrong...please forgive me...attached the actual question..We must write down the model class.View attachment 35743
The answer is:
View attachment 35745
Why greater than 20, but smaller AND equal to 25?

That would be because of how the ogive (cumulative distribution function) is defined!

Please show the definition you were given. Most likely it is something like this:

Cumulative distribution function - Wikipedia

en.wikipedia.org

(Note the [imath]\le[/imath] symbol in equations 1 and 2.)

Questions like yours are touched upon here, as well:

Cumulative Distribution Functions (Ogive) – The Math Doctors

www.themathdoctors.org

But please note, the word is spelled "modal"; "model" is a very different word, in both pronunciation and meaning. If you show us the entire problem, as requested, you should see that in the question.

Also, the symbol you are asking about means "less than or equal", not "less than and equal".