In a company 3/5 of people know shorthand 1/4th know typing and 1/5 know both. What fraction of people do not know both..

• p(shorthand)=3/5 ,p(typing)=1/4
  p(shorthand ∩ typing)=1/5
  now
  p(shorthand u typing)=3/5+1/4-1/5=13/20
  so 1-13/20=7/20 fraction of people do not know both .
• 11 years agoHelpfull: Yes(86) No(3)
• Let A = 3/5
  B = 1/4
  A intersect B = 1/5
  A union B = 3/5 + 1/4 -1/5 = 13/20
  The no of people who do not know both = 1- (13/20) = 7/20
• 11 years agoHelpfull: Yes(12) No(0)
• answer= 7/20
  
• 11 years agoHelpfull: Yes(3) No(0)
• use venn diagram:
  p(shorthand & both)=3/5
  p(both)=1/5
  p(shorthand)=3/5 -1/5 =2/5
  -----p(typing & both)=1/4
  then p(typing)=1/4 -1/5=1/20
  p(do not know both)=(2/5) + (1/20) =9/20(ans)
• 11 years agoHelpfull: Yes(2) No(6)
• total no.of shorthanders n(A)=3/5
  total no.of typist n(B)=1/4
  know both shorthand, typing n(A ∩ B) =1/5
  using formula n(A U B)=n(A)+n(B)-n(A ∩ B)
  total number n(A U B)= 3/5+1/4-1/5=13/20
  so do not know both=((n(A)+n(B)+n(A∩B))-n(AUB)
  =21/20-13/20=2/5
  
• 11 years agoHelpfull: Yes(1) No(29)
• know no catagory=know single catagory-know all catagory
  =(3/4+1/4)-1/5
  =13/20(ans)
• 11 years agoHelpfull: Yes(1) No(14)
• consider any random number take as 20 now people know shorthand is (3/5)*20=12 typing is 5 know both is 4 hence people dont know both is 16/20=0.8
• 9 years agoHelpfull: Yes(1) No(1)
• knows only shorthand=3/5-1/5=2/5
  knows only typing=1/4-1/5=1/20
  therefore fraction of people not knowing both=2/5+1/20=9/20(ans)
• 11 years agoHelpfull: Yes(0) No(8)