10 speakers gathered to deliver speeches on two topics.

Question

10 speakers gathered to deliver speeches on two topics. Even though 10 speeches were initially planned to be delivered, due to lack of time only 2 speeches were finally decided to be delivered. Topics are to be spoken in a specific order and the speeches differ with respect to speaker or topic. How many such two speeches are possible?

A. 2
B. 20
C. 50
D. 100
E. 1024

A. 2
B. 20
C. 50
D. 100
E. 1024

chetan2u · Answer

Hi,
the words are a bit confusing..
But What I could gather..
 
1)there are 10 speeches in ONE topic and 10 in OTHER..
2)there is a specific order for topics, so 
---a) both the topicd are to be spoken on- so ONE from each
---b) the order does not matter since there is ONLY one specific order..

so  10C1*10C1 = 10*10 = 100 
D

SVaidyaraman · Answer

Hi,

Some clarifications:

1. There are only 2 speeches and not 10 speeches
2. One speech is on 1 topic and the other speech is on the other topic
3. The order of the topics is fixed . So if the topics are A and B, the order may be fixed as A,B
4. The same speaker may speak on both the topics.

chetan2u · Answer

thanks  SravnaTestPrep ..
so 2 speeches - ONE on each topic.. But as I mentioned above that since there is a specific order, arrangement or Permutations is not required..
first speech can be spoken by any of the 10 followed by the 2nd speech by any of the 10 - so 10*10 = 100

hongson1706 · Answer

i think the problem is confusing

rekhabishop · Answer

Pathetic question. The words don't make any sense. Such question are disparaging for a newbie. For us, every question is a potential gmat question because we're on a GMAT forum!!!

SVaidyaraman · Answer

Dear rekhabishop,

I am sorry that you did not find the question up to the mark. I will ensure that the quality of the question is always maintained. Btw, have you tried our other questions posted on the forum?

JeffTargetTestPrep · Answer

The number of choices for the first speech is 10 and the number of choices for the second speech is also 10. Thus, the number of ways two speeches can be delivered is 10 x 10 = 100.

Answer: D

devarshi9283 · Answer

"the speeches differ with respect to speaker or topic"

If this is the case then how can second speech be selected in 10 ways....Plz Explain  SravnaTestPrep

SVaidyaraman · Answer

Let us say the topics are S and T. Since the order of the topics spoken is fixed, let us assume it is S first and T second. Now S can be spoken by any of the 10 speakers. Then T can be spoken by any of the 10 speakers, for a total of 10*10=100 speeches.

devarshi9283 · Answer

But if  speeches differ with respect to speaker  ...If this sentence is referring to 2 speeches that are to be delivered ..then how come same speaker give a speech for second topic..
as far as i understand...the second speech may be delivered by 9 speakers only excluding the one speaker who has just finished with 
first speech...

or may be "speeches differ with respect to speaker and topic" is said to indicate that all speeches are unique...in that case...this should have been told at the start of question itself...it's really confusing

SVaidyaraman · Answer

The speaker who spoke on the first topic can also speak on the second topic. That I believe is implied by the sentence that speeches differ with respect to speaker or topic. So, the speaker who spoke on the first topic and also speaking on the second topic implies that the speeches differ with respect to topic.

notgivingupami · Answer

"Topics are to be spoken in a specific order and the speeches differ with respect to speaker or topic." This is a rather confusing line.

Kinshook · Answer

Given: 10 speakers gathered to deliver speeches on two topics. Even though 10 speeches were initially planned to be delivered, due to lack of time only 2 speeches were finally decided to be delivered. Topics are to be spoken in a specific order and the speeches differ with respect to speaker or topic.

Asked: How many such two speeches are possible?

Number of speeches possible = 10*10 = 100

IMO D

Asked: How many such two speeches are possible?

Number of speeches possible = 10*10 = 100

IMO D

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10 speakers gathered to deliver speeches on two topics.

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10 speakers gathered to deliver speeches on two topics.

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