Elitmus
Exam
In a certain examination paper there are n questions.For j=1,2,3,4.............n there are 2^n-1 students who answered j or more questions correctly.If total number of wrong answers is 4095 then the value of n is
A)12
B)11
C)10
D)9
Read Solution (Total 5)
-
- The correct answer is 12 as it is given here that 2^n-1 students answered j questions correctly
=> 2^n-1=4095
we know 2^12=4096
i.e 4096-(2^12)1=4095 - 11 years agoHelpfull: Yes(6) No(9)
- @sumit,,
they have given 4095 for wrong answers na,,
then you equated it with 2^n-1 (which is the number of correct answers)
how it will be?
could you explain me indetail? - 10 years agoHelpfull: Yes(3) No(0)
- @sumit rawal please explain.
- 11 years agoHelpfull: Yes(0) No(0)
- It should be 2^(n-j)
then n=12 - 11 years agoHelpfull: Yes(0) No(2)
- @sumit pls explain me correctly...
- 10 years agoHelpfull: Yes(0) No(0)
Elitmus Other Question
PT Usha and Shelly John decided to run a marathon between RamNagar and JamNagar.Both start from RamNagar at 1 Pm. On the way there are two towns RamGadh and Rampur. separated by a distance of 15KM.PT USHA reaches RamGadh in 90 minutes running at a constant speed of 40 KM/h.She takes additional 30 minutes to reach Rampur,Between Rampur and JamNagar she maintains an average speed of VKm/h.(where v is a whole number).Shelly John being a professional Marathan runner, maintains a constant speed of 18Km/hour.They both reach RamNagar together after n hours n being a whole number.What could be the total time taken by PT USHA??
A)5
B)15
C)41
D)All of the above
Saqueed and khajid are gamblers.They love betting on final team rankings in cricket tournaments.LPI cricket tournament is their favourite.A total of 5 teams are participating in this year LPI(A,B,C,D,E).Before the tournament begins Sajeed and Majeed get the result.According to the sajeed the result should be A,B,C,D,E and according to Majeed the ranking should be D,A,E,C,B.At the end of tournament it turned out that Sajid has not predicted even a single rank correctly nor had he pridected the correct ordering of any pair of consecutive teams.On the other hand, Majeed had predicted the rankings of two teams correctly and he has also predicted ordering of two pairs of consecutive teams.
Which team won LPI tournament this year?
A)A
B)B
C)E
D)None of the above
Which team was ranked one behind B?
A)A
B)C
C)D
D)None of the above