CTS
Company
A secret can be told to only 2 persons in 3 minutes. Each person in turn tells 2 other persons in the next 3 minutes and the processes continues accordingly. In 30 minutes how many persons can be told this secret in this way?
a) 1024 b) 2048 c) 512 d) 4096
Read Solution (Total 5)
-
- 2^1 + 2^2 + 2^3 + 2^4 + ..............+2^10 =>2048(b)Ans.
- 11 years agoHelpfull: Yes(2) No(0)
- in 3 min 1 person say the secret to 2 people.
in 6 min (1+2=3) peroson say the secret to 6 people
in 9 min (3=6=9)person say the secret to 18 people.
see each n every time the no is multiplied by 3.(ie2 then 6 then 18)
so total no of person knw the secret in nxt 31 min=18*3^7=39366
so similarly - 11 years agoHelpfull: Yes(0) No(1)
- 2^10=1024
remaining is same as manish sir solution
- 10 years agoHelpfull: Yes(0) No(0)
- IN 3 MIN 2
IN 6 MIN 4
.
.
.IN 30 MIN 1024 (ANS) - 8 years agoHelpfull: Yes(0) No(0)
- 2^1 + 2^2 + 2^3 + 2^4 + ..............+2^10 = 2(2^10 - 1)/(2-1)
= 2*1023 = 2046 - 8 years agoHelpfull: Yes(0) No(0)
CTS Other Question