There are 6 Questions on a question paper. In how many ways can a student solve one or more questions?
a)6 b)12 c)63 d)64 e)65
There are 6 Questions on a question paper. In how many ways can a student solve one or more questions?
a)6 b)12 c)63 d)64 e)65


is it 63
shanmukh
Thanks guys for your reply.
Answer is (C). But I don't understand the way you reach that.
Why do you subtract 1 from 2^6?
And the Q asks in how many ways can you solve ONE OR MORE QUESTIONS?
What does it mean - the ways to solve all 6 Questions, or just one + some more, but how many??
I am totally confused with this one... PLease, help
2^6 - 1 is the shortest way, though understanding the mechanics is important.
Total Combinations = nCr.
Where n = 6.
r = 1..6. (no zero because, atleast one question has to be solved)
so 6C1+6C2+...+6C6 = 63.
Thank you Scorer!!!Originally Posted by scorer
It is much, much clear now![]()
how did u get 2^6?? Please help !! Thnx
Look at it like this
there are 2 options with each question
1. u solve it
2. u dont solve it
so possible ways are 2 for each question
now if u have 2 questions
possible ways =2*2
extend the logic to 6 q's
possible ways = 2^6
hope it clears some doubts
n we reduce the 1 in the answer...
well im sure every1 knows that by now
uday
2 dumb Qs here.
1) nCr. how does this work? 6C1 = ? 6C2 = ?
2) why do we minus 1? uday, sorry, i just want to confirm it. Is it because we have to answer at least 1 correct answer? so getting all 6 wrongs is not an option.
Please Correct my answers/POE method/reasonings in my post if you can.....
Thanks!
Also, Anyone in Philadelphia Region would like to get together and study or who with proven record is able to tutor me on weekends, Please PM me. Willing to pay for some tutoring.
GMAT Crushed me......
Now, I need help....
Why the hell I did not find this site before GMAT crushed me...........
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