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Saumyojit

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A bag contains 4 mangoes and 5 oranges .In how many ways can I make a selection so as to take at least one from each.


All mangoes orange are alike .

So , I put 4 mangoes in one basket and 5 in another.

Mmmm Ooooo

From the mangoes basket I can select *any* one or two or three or four --->(1+2+3+4)

Similarly for orange (1+2+3+4+5)

Both events of selection will happen simultaneously,
10*15=150 ??


If all are Distinct then 2^9 -1

Both ways Answer is not coming
 
Saumyojit said:
A bag contains 4 mangoes and 5 oranges .In how many ways can I make a selection so as to take at least one from each.

All mangoes orange are alike .

So , I put 4 mangoes in one basket and 5 in another.

Mmmm Ooooo

From the mangoes basket I can select *any* one or two or three or four --->(1+2+3+4)

Similarly for orange (1+2+3+4+5)

Both events of selection will happen simultaneously,
10*15=150 ??

If all are Distinct then 2^9 -1

Both ways Answer is not coming
Click to expand...
I suppose "All mangoes orange are alike" is supposed to mean that the mangos are indistinguishable, as are the oranges. What you wrote is not English; can you show us the original wording, exactly?

So the bag contains MMMMOOOOO. (All alike.) It doesn't matter which ones you take, only how many.

Why do you add 1+2+3+4?

Why do you suggest that all are distinct, when you are told that they are alike, and therefore not distinct?

There are 4 ways to choose a number of mangos to take (1, 2, 3, or 4), and 5 ways to choose a number of oranges to take (1, 2, 3, 4, or 5), for a total of 4*5 = 20:

Code: 
MO     MOO     MOOO     MOOOO     MOOOOO
MMO    MMOO    MMOOO    MMOOOO    MMOOOOO
MMMO   MMMOO   MMMOOO   MMMOOOO   MMMOOOOO
MMMMO  MMMMOO  MMMMOOO  MMMMOOOO  MMMMOOOOO

When you say "Answer is not coming", what do you mean? That you can't find an answer, or that you know the "correct" answer and don't get that, or something else?
 
Dr.Peterson said:
I suppose "All mangoes orange are alike" is supposed to mean that the mangos are indistinguishable, as are the oranges. What you wrote is not English; can you show us the original wording, exactly?

So the bag contains MMMMOOOOO. (All alike.) It doesn't matter which ones you take, only how many.

Why do you add 1+2+3+4?

Why do you suggest that all are distinct, when you are told that they are alike, and therefore not distinct?

There are 4 ways to choose a number of mangos to take (1, 2, 3, or 4), and 5 ways to choose a number of oranges to take (1, 2, 3, 4, or 5), for a total of 4*5 = 20:

Code: 
MO     MOO     MOOO     MOOOO     MOOOOO
MMO    MMOO    MMOOO    MMOOOO    MMOOOOO
MMMO   MMMOO   MMMOOO   MMMOOOO   MMMOOOOO
MMMMO  MMMMOO  MMMMOOO  MMMMOOOO  MMMMOOOOO

When you say "Answer is not coming", what do you mean? That you can't find an answer, or that you know the "correct" answer and don't get that, or something else?
Click to expand...
I have written there both the cases .
Yes I know the answer.

One case can be all mangoes are Alike and all oranges alike.
And another case is all mangoes are distinct and similarly all Oranges.

I added them as I was thinking like this

Either one Mango or two or three or four.
So, or means addition.
So 1+2+3+4 .
But it should be 4 .

As they are four ways only.


Answer is not 20.
I am also confused.
 
Okay I understood they have assumed all are distinct.
2^9 -1 will not work as it can happen either no Mango and atleast one orange is selected .

I did it by simple combination ?
 
Saumyojit said:
Either one Mango or two or three or four.
So, or means addition.
So 1+2+3+4 .
But it should be 4 .
Click to expand...
No, "or" doesn't mean addition, any more than "and" means addition. The addition associated with "or" means adding probabilities, or number of possibilities, if things are mutually exclusive. That is not what you did. Always think.

Saumyojit said:
Answer is not 20.
I am also confused.
Click to expand...
So you're saying your source gave an answer? Please quote the exact problem from the source, as I asked, and also quote their claimed answer. Maybe they are wrong, and we'd be wasting our time if we wait until you say we have the "correct" answer.

Saumyojit said:
Okay I understood they have assumed all are distinct.
Click to expand...
But it says the opposite -- unless you have quoted the problem inaccurately. Apparently you did, so why should we waste any time on this?

Well, suppose the part about "all alike" was your own faulty assumption, not part of the problem, and they intended the mangos to be distinguishable, though they didn't explicitly say so. Then why not do what you did for the last problem? How many ways are there to choose a non-empty subset of the mangos? How about a non-empty subset of oranges? Now combine those.
 
Saumyojit said:
A bag contains 4 mangoes and 5 oranges .In how many ways can I make a selection so as to take at least one from each. All mangoes [& all] orange are alike .
Click to expand...
Prof Peterson has rightly commented on your English usage, as written I claim the answer is twenty.
Here is a listing of how we can make the selections of each:
\(\large\bf\{M\},\{M,M\},\{M,M,M\},\{M,M,M,M\}\) and then oranges \(\large\bf\{O\},\{O,O\},\{O,O,O\},\{O,O,O,O\},\{O,O,O,O,O\}\)
Four ways to pick the mangoes & five ways to pick the oranges.
 
We have rules. One is to quote the problem exactly and completely.

Why should anyone here help you when you persistently refuse to follow the rules?

You frequently ask “why is my answer wrong.” That implies you know what someone said was the correct answer. That someone may have had the wrong answer, and your answer may be correct. Nor do you give detailed descriptions of your logic along with computations. Frankly, I see no reason to answer what may be meaningless and are definitely vague questions.

I am putting you on “ignore.”
 
JeffM said:
We have rules. One is to quote the problem exactly and completely.

Why should anyone here help you when you persistently refuse to follow the rules?

You frequently ask “why is my answer wrong.” That implies you know what someone said was the correct answer. That someone may have had the wrong answer, and your answer may be correct. Nor do you give detailed descriptions of your logic along with computations. Frankly, I see no reason to answer what may be meaningless and are definitely vague questions.

I am putting you on “ignore.”
Click to expand...
I say my answer is wrong because after my first try at solving the question , the answer does not match with the book's Answer.
As simple as that, so it means I have done something wrong in my approach.

What's so vague about this?

And the question that I can give are correct why do you doubt it ?
 
Saumyojit said:
I say my answer is wrong because after my first try at solving the question , the answer does not match with the book's Answer.
As simple as that, so it means I have done something wrong in my approach.
Click to expand...
When you know the supposed answer, you are expected to state it. That's been said several times. You still haven't done that. That is the first issue.

Saumyojit said:
Where did you see I quote the problem wrong.
The question that was given was absolutely right . No mistake

You can Google it .?
Click to expand...
It appeared at first that your statement about all being alike was part of the (paraphrased) problem, so we assumed it was given. In that sense you quoted the problem incorrectly. It is important to make it clear what part of what you write is the actual problem.

I just now googled it, and found it in many places. How am I to know which you read? And why do I need to make that effort? I sometimes do that when I am not sure of some aspect of a question; I haven't done that in this case. I apologize for being negligent. (Not) Not knowing which site you looked at means I can't know whether it is an answer, or some particular solution, or something else, that you are comparing your work to. It wastes our time having to guess such things.

When you find a problem somewhere and want to ask why your own solution doesn't work, you should make all that clear by giving a reference to the problem so we can see what you have read, stating explicitly that your issue is that the answer doesn't match what you were given, and perhaps asking specific questions about your work in comparison to what you have read.

Your not doing so is disrespectful, along with other aspects of your behavior.

Dr.Peterson said:
Then why not do what you did for the last problem? How many ways are there to choose a non-empty subset of the mangos? How about a non-empty subset of oranges? Now combine those.
Click to expand...
Now, why haven't you responded to this, which gets to the real issue? Does it help? Does it give you whatever answer you are expecting?
 
I just took the time to look at a couple of the hits I got for the problem, and the situation is worse than I thought. Look at these cases:

APC CBSE Mathematics - Class 11 - Avichal Publishing Company

1625666249947.png​

Stack Exchange

1625666455625.png​

So different books present the same exact problem and interpret it different ways!

Sometimes the hardest part of math is the English. And the real problem is in the writing, not the reading.
 
Dr.Peterson said:
I just took the time to look at a couple of the hits I got for the problem, and the situation is worse than I thought. Look at these cases:

APC CBSE Mathematics - Class 11 - Avichal Publishing Company


Stack Exchange


So different books present the same exact problem and interpret it different ways!

Sometimes the hardest part of math is the English. And the real problem is in the writing, not the reading.
Click to expand...
Both are right one is alike another is all distinct.
That is what I was telling you!
 
Well, no. Both can't be right.

Both answers are correct, depending on your interpretation of the problem, but a problem that can be interpreted both ways clearly is not well written, and both authors failed to correct it (whatever their own source might have been). So both problems are wrong.

Do you still refuse to tell us what your own source was, and what answer you were thinking was correct? From your OP, I have to surmise that your source said they were alike; but then they would have given the answer of 20. So at the least, it appears that you didn't pay attention to what you read.
 
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