There are 2 persons A and B. A select 2 numbers from the set { 3,4,5,6,7}. There are 2 sets { 5,7,19,23,34} and {13,24,4,56,11}. B selects 1 no. from any one of the set . What is the probability that the no. chosen by B is greater than the sum of the 2 numbers selected by A.

• There can be 5C2=10 combinations when 2 numbers are selected from A.
  The sum of the 2 numbers are between : 7 to 13.
  so,we have to consider each case from 7 to 13 when 2 numbers are selected.
  
  When sum=7 : probability of selecting sum 7 from A = 1/10 (obtained when {3,4} is selected).After that,probability of selecting a set from B us 1/2.
  And when sum 7 we need to select (19,23,34) from set 1 and (13,24,56,11) from set 2. So, total probab = 1/10*[(1/2*3/5)+(1/2*4/5)] = 7/100 .
  
  Similarly,we need to find the cases for the rest of the sums 8 to 13.
  
  Total 65/100 will come rounded to 13/20(Ans).
  
• 11 years agoHelpfull: Yes(14) No(0)
• ans is 1/2
  
  
• 11 years agoHelpfull: Yes(9) No(2)
• ans is 59/100...
  
• 11 years agoHelpfull: Yes(2) No(4)
• a select number it's sum is atmost=13
  so b select number greater then 13
  hence
  5c2/(5c3+5c2)=10/20=1/2
  hence ans=1/2;
  is it right??
• 11 years agoHelpfull: Yes(2) No(1)
• total 65 cases .... so it should 65/100 i.e. 13/20
• 11 years agoHelpfull: Yes(2) No(0)
• A can select {3,4},{3,5},{3,6},{3,7},{4,5},{4,6},{4,7},{5,6},{5,7},{6,7} total 10 ways.
  B can select from {5,7,19,23,34,13,24,4,56,11}
  then B select greater than 7
  then probablity is 7/11
• 11 years agoHelpfull: Yes(2) No(1)
• ANS IS 5/10 =1/2;A A SELECTS SET OF NUMBER OF SUM IN SUCH WAY,(7,9,11,13,10,11,12,9,10,8),REMOVING THESE FROM SET OF B SELECTION.
• 11 years agoHelpfull: Yes(2) No(0)
• ans is 41/50
• 11 years agoHelpfull: Yes(1) No(8)
• Pls explain the solution of this problem.
• 11 years agoHelpfull: Yes(1) No(3)
• sorry, there is mistake in my previous approach.
• 11 years agoHelpfull: Yes(1) No(0)
• ans is 13/20
• 11 years agoHelpfull: Yes(1) No(1)
• ans is 13/20
• 11 years agoHelpfull: Yes(1) No(0)
• A can select a no in 5c2 ways.
  B has to choose a set a then select a no which is greater than the sum of those two no alredy chosen by A(which could max be 13).Therefore, 1/2*3c1(19,23,24 from one set)+2c1(56,24) ways.
  hence req probability=(1/2*(3c1+2c1))/5c2=1/4.
• 11 years agoHelpfull: Yes(1) No(0)
• correct ans is 9/20
  procedure
  we can first select the numbers in 100 ways so
  sample space=100
  now the sum of two numbers given by A will be
  either 7 or 8 or 9 or 10 or 11 or 12 or 13
  when sum is 7 then we can select any 7 numbers for B
  when sum is 8 we can select again 7 numbers for B
  when sum is 9 .................... 7 ............
  when sum is 10 ....................7.............
  when sum is 11 ...................6.............
  when sum is 12 ...................6.............
  when sum is 13....................5.............
  so total =45
  hence probablity =45/100
  ====9/20
  
• 11 years agoHelpfull: Yes(1) No(2)
• please explain the procedure
• 11 years agoHelpfull: Yes(0) No(1)
• A can select two numbers as
  i. 3+4=7; ii. 3+5=8; iii. 3+6=9; iv. 3+7=10;
  v. 4+5=9; vi. 4+6=10; vii. 4+7=11;
  viii. 5+6=11; ix. 5+7=12; 6+7=13
  So probability of case i,ii,iii,iv,v,vi is like selecting one number from
  19,23.,34,13,24,56,11 i.e., 1/7 for each case and for all 6cases 6/7
  Probability of case vii,viii,ix is one from 19,23,34,13,24,56 i.e., 1/6 for each
  and 3/6 fo all three.
  prob. of last case is 1/5
  therefore 6/7+3/6+1/5=327/210= 109/70 ans.
• 11 years agoHelpfull: Yes(0) No(15)
• 5C1/10C1=1/2
• 11 years agoHelpfull: Yes(0) No(1)
• A can choose 2 numbers out of 5 numbers in 5C2 ways.in such cases sum of 2 numbers is between 7 to 13.now B can choose 5 which is less than 7 and the probability is 1/10.
  so,probability that number choosen by B is greater than sum of the numbers of A is 1-1/10=9/10.
  
• 11 years agoHelpfull: Yes(0) No(2)
• A can select {3,4},{3,5},{3,6},{3,7},{4,5},{4,6},{4,7},{5,6},{5,7},{6,7} total 10 ways.
  B can select from {5,7,19,23,34,13,24,4,56,11}
  then B select greater than 7
  then probablity is 7/11
  
• 10 years agoHelpfull: Yes(0) No(0)