Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at random. What is the probability that the ticket drawn has a number which is a multiple of 3 or 5?

Options
1) 1/2
2) 2/5
3) 8/15
4) 9/20

• Here, S = {1, 2, 3, 4, ...., 19, 20}.
  
  Let E = event of getting a multiple of 3 or 5 = {3, 6 , 9, 12, 15, 18, 5, 10, 20}.
  9/20
• 9 years agoHelpfull: Yes(11) No(0)
• 24 times
  as D/d=n/N
  so for 1 sec 54/32=45*n/80 or n= 3 times in 1 sec
  so in 8 sec, 3*8=24 times
  
• 9 years agoHelpfull: Yes(2) No(5)
• ans.128..
  exp-80*3/15*60=960.
  960/60*8=128
  
• 11 years agoHelpfull: Yes(1) No(2)
• Less Cogs => more turns and less time => less turns
  
  cogs time turns
  A 54 45 80
  B 32 8 ?
  
  
  Number of turns required = (80 * 54 * 8)/(32 * 45) = 24 times
• 9 years agoHelpfull: Yes(1) No(2)
• Less Cogs => more turns and less time => less turns
  
  cogs time turns
  A 54 45 80
  B 32 8 ?
  
  
  Number of turns required = (80 * 54 * 8)/(32 * 45) = 24 times
• 9 years agoHelpfull: Yes(1) No(0)
• 9/20 will be the ans.
  multiple of 3 are 3,6,9,12,15,18 & multiple of 5 are 5,10,15,20.
  total multiple is 9.
• 7 years agoHelpfull: Yes(0) No(0)