A basket ball is dropped from hight at 24 feet it bounce back each time to a height which is one half of the height of the last bounce.how for approxmately will the ball have traveled before it comes ?

a) 12 b) 24 c) 72 d)can't be deteremined

• ANS: c)72
  
  24+(12+12)+(6+6)+(3+3)+.......
  = 24+2*[12+6+3.....]
  = 24+2*[12/(1-1/2)] (INFINITE GP a/(1-r))
  = 24+48
  = 72
• 9 years agoHelpfull: Yes(53) No(0)
• as it has been dropped from 24 feet so the ball will travell approximately
  = 24 + (12+12)+ (6+6)+(3+3) + (1.5+1.5)+ (.75+.75)....
  = 72
• 9 years agoHelpfull: Yes(4) No(1)
• when the ball is dropped it first travel 24 feet in downwards direction then it bounces back again upto 24 feet then then after every bounce its height reduces by 1/2 i.e
  24+[24+12+6+3+2+1+....]
  its in g.p and has infinite terms so
  s= 24/(1-1/2)
  s=48
  total=48+24
  i.e 72 option c
• 9 years agoHelpfull: Yes(4) No(0)
• here the height is decreased by half ..so consider r = 1/2..
  first term is 24 and scond term will be 12..
  so the formula for this type of Geometric progression is
  (first term/(1-r))+(second term/(1-r))
  i.e 24/(1/2) + 12(1/2) = 48+24 = 72..ans c)72
• 9 years agoHelpfull: Yes(2) No(0)
• ANSWER==>72
  1st bounce to 24 feet
  2nd bounce to 12 feet
  it will continue till comes to rest. So its a infinite GP.
  24/(1-1/2)+12/(1-1/2)=72 feet
• 9 years agoHelpfull: Yes(2) No(0)
• it will be =24+2*24( 1/2 + (1/2)^2 upto infinity)
  24+48* (1/2)/1-(1/2)=72
• 9 years agoHelpfull: Yes(1) No(0)
• 24+12+12+6+6+3+3+1.5+1.5+0.75+0.75+0.3+0.3~=72
• 9 years agoHelpfull: Yes(1) No(0)
• This forms the infinite gp so 24*2 + 12*2 =72
• 9 years agoHelpfull: Yes(1) No(0)
• Total Disatance Travveled by the ball = 24+(12+12)+(6+6)+(3+3)+............
  so, 24+2*(12+6+3+........)
  24+2*[12/(1-1/2)]
  24+48
  72 Ans
• 9 years agoHelpfull: Yes(1) No(0)
• 24 12 12 6 6 3 3...
  24+(24+12+6+....)
  24+(24/(1-.5))=24+48=72
• 9 years agoHelpfull: Yes(0) No(0)
• 72 Each time the ball bouces to half the height , so form a geometric progression with first term 24 and common ratio 1/2 upto infinity . the sum of an infite G.P is the answer .
• 9 years agoHelpfull: Yes(0) No(0)
• it will be a geometric progression. and the distance =24+2*(24/2+24/4+24/8+24/16 +24/32+.......)
  distance D=24*(1+2*(1/2+1/4+1/8+1/16+........)
  D=24*(1+2*(0.5/(1-0.5))=24*(1+2)=72 answer.
• 8 years agoHelpfull: Yes(0) No(0)
• can't be determined :)
• 8 years agoHelpfull: Yes(0) No(8)
• 72 approx becoz 24+(24/2)*2+(12/2)*2+(6/2)*2+(3/2)*2+(1.5/2)*2+(.75/2)*2=71.625
  we multiply by 2 becoz it bounce and cm back by covering same distance and divide by 2 becoz it always bounce half of previous distance
• 7 years agoHelpfull: Yes(0) No(0)
• #Trick given 24feet and bounce back 1/2
  
  so 24*(1+2)/ (2-1)=72
• 7 years agoHelpfull: Yes(0) No(0)