Q. 25% students of a class failed in Chemistry and 40% failed in Physics where 10% did not pass in any of the two subjects. If 30 students passed in only Physics, how many of them passed in both the subjects.

• n(C)=75% , n(P)=60% , n(PUC)= 90% => n(PnC)= 75% + 60% - 90% = 45%. given n(P) - n(PnC)= 30 , 60% - 45% = 30 => 15% = 30 => 1% = 2 . n(PnC) = 45% = 90
• 11 years agoHelpfull: Yes(8) No(5)
• n(C fail)=25% => n(c pass)=75,
  n(p fail)=40% => n(p pass)=60,
  n(PUC fail)= 10% =>n(PUC pass)= 90%,
  n(PnC pass)= n(p pass)+n(c pass)-n(PUC pass)=75% + 60% - 90% = 45%.
  we have n(P pass) - n(PnC pass)= 30,
  => 60% - 45% = 30
  => 15% = 30
  =>1%=2,
  n(PnC pass) = 45%
  =>2*45=90. ans=90.
• 11 years agoHelpfull: Yes(6) No(0)
• 25x/100+40x/100-10x/100=11x/20 , x-11x/20=9x/20, 25%of x - 10% of x=no. of people passed in physics=30(given), now x=200, from that 9x/20=90 ans.
• 11 years agoHelpfull: Yes(2) No(0)
• 30 students passed only in physics means failed in chemistry
  so total chemistry failures - both failures gives only chemistry failures
  (25%-10%)x = 30 => 15%x=30 => x=200
  toatal pass = 100%-25%-40% =35%
  35%= 70 students passed in both
• 10 years agoHelpfull: Yes(1) No(2)
• bhai koi easy way me batao please..
• 11 years agoHelpfull: Yes(0) No(3)
• n(C fail)=25%, n(C pass)=75%
  n(P fail)=40%, n(P pass)=60%
  n(both fail)=10%, n(any 1 pass)=90%
  n(passd only physics)=n(any 1 pass)-n(P pass)
  30 =90%-60%
  30=15x/100
  x=200
  n(all pass)=n(P pass)+ n(C pass)-n(any 1 pass)
  =60%+75%-90%
  =45%
  hence, (45*200)/100= 90
• 11 years agoHelpfull: Yes(0) No(0)