Dan has a membership at a local gym that also gives classes three nigh

Question

Dan has a membership at a local gym that also gives classes three nights a week. On any given class night, Dan has the option of taking yoga, weight training, or kickboxing classes. If Dan decides to go to either one or two classes per week, how many different combinations of classes are available?

A. 3
B. 6
C. 7
D. 9
E. 12

A. 3
B. 6
C. 7
D. 9
E. 12

msk0657 · Answer

Dan has the option of taking one class or two classes per week.

If Dan takes  one class per week  then he can give training out of any three course...i.e 3C1 . Total possibilibiliy = 3.

If Dan takes  two classes per week  then he can give training out of three three course on first class ...i.e  3c1 = 3 - First class 
 he can give training out of three three course on second class ...i.e  3c1 = 3 - Second class..

When we add this we get total 9 possibilities...

IMO option D is correct answer...

OA please...will correct if I missed anything..

BrentGMATPrepNow · Answer

ALWAYS check the answer choices before starting any calculations. 
Here the answer choices are all quite small, so we might just consider  listing and counting  all of the possible outcomes.

Let A, B and C represent the nights of the week when classes are offered. 
Let Y, W and K represent yoga, weight training, and kickboxing

Now consider the possible outcomes if Dan decides to go to  one  class per week. 
We get the following: 
AY 
AW
AK
BY
BW
BK
CY
CW
CK
TOTAL = 9 possibilities

Of course, that's just considering  one  class per week. 
If we add a second class, there will be MORE THAN 9 possibilities.

Answer:  E

RELATED VIDEO 
 https://www.youtube.com/watch?v=KGvBUx3FUWQ

MarkusKarl · Answer

I am clearly getting a wrong answer.

If dan decides to Go to one class he has 9 choices.
Night 1, 2 or 3 and class a, b or c.

If dan decides to Go to two classes he can combine the classes in 9*8=72 ways.

If we add them up we get 81.

I Think i am missing something essential here. Do we not differentiate between the days or the type of classes?

Posted from my mobile device

abhimahna · Answer

I think it should be E only.

No where it is given that he attends different classes on each day.

Experts please provide your views.

--- EDITED my Response. It was a typo. I meant 12 is the answer.

If only Day 1 : 3 options

If Day 1 and Day 2 : 3*3 = 9 Options

So, Total = 3+9= 12.

tanmay056 · Answer

Isn't the answer is - E ?...because it says either one or two classes ....If we consider 1 class per week , then it's - 9 whereas if we consider 2 classes per week, then it would become - 12 ......Experts please help which one to take ........

sumitsinha4u · Answer

Answer - D.

1 Week - Three Option. 
or 2 week - 6 option .
Total :- 9.

Thanks

dhanyamv88 · Answer

Hi Bunuel,

Please help with the solution. I got the answer as 6

If it is 1 class - Y/W/K - 3 options and If It is 2 class - YW,WK and KY - 3 options again

So total of 6. I am not sure what I missed?

Bunuel · Answer

Check here: dan-has-a-membership-at-a-local-gym-that-also-gives-classes-three-nigh-223916.html#p1724428

NaeemHasan · Answer

Hi Bunuel,
Could you, please, give your own solution. The explanation that you have referred says the answer is E. But in the original Post you have added OA D. Hope, your explanation will remove all controversies.

Dan has a membership at a local gym that also gives classes three nigh

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