The number is given O such that O is greater than equal to 7. Square of the number O is S. Find the probability that (S-1) is divisible by 24

• In this question unless the extent of number is not given we can not find the answer. All prime satisfy this condition but we dont know the maximum limit.
  
  or there may be some option to support that.
• 11 years agoHelpfull: Yes(20) No(0)
• let take 7 at first 7^2 - 1= 48 yes divisible
  8^2 -1 = 63 no
  9^2 -1 = 80 no
  10^2 -1 = 99 no
  11^2 -1 = 120 yes
  so in every 4 consecutive terms....there comes a multiple of 24 so answer is 1/4
• 11 years agoHelpfull: Yes(12) No(33)
• the probability should be 1/3.
• 11 years agoHelpfull: Yes(4) No(0)
• s=square of all prime no.
  so we can not determine
  the probability unless someone knows the probability of finding a prime no. in integer.
• 11 years agoHelpfull: Yes(3) No(2)
• options were a)1/3 b)3/5 c)3/7 one option i forgot
  but cannot be determined and 1/2 these two option were not there..
• 11 years agoHelpfull: Yes(2) No(0)
• @sahil i dont think ur answer is correct....... this condition apply on all prime no. all prime square-1 is divisible by 24
• 11 years agoHelpfull: Yes(2) No(1)
• 3/7 because out of 10 number from 7 to 16 there is 7 11 13 which satisfied
• 11 years agoHelpfull: Yes(2) No(1)
• 48(*) 120(*) 224 360(*) 528(*) 728
  63 143 255 399 575 783
  80 168(*) 288 440 624(*) 840(*)
  99 195 323 483 675 899
  For every 12 values of (n^2 - 1) 4 are divisible by 24
  So ans is (4/12) = 1/3
• 11 years agoHelpfull: Yes(2) No(0)
• Events E={48,120,288,360,.......}=(S-1)/24 and
  0={7,11,13,17,19,........}=all prime nos.
  no. of events n(E)=?=no. of prime nos. from 7 to infinite.
  no. of sample space n(s)=?={24,48,72,96,120,144,168,192,216,240.......}
  give me some suggestion.
• 11 years agoHelpfull: Yes(1) No(1)
• may be 1/2
  
  plz show the options
• 11 years agoHelpfull: Yes(0) No(2)
• i didn't remember the option bt definitely der was no option like cannot be determined
• 11 years agoHelpfull: Yes(0) No(0)
• Mr Sahil i think u r right
• 11 years agoHelpfull: Yes(0) No(6)