The price of groudnuts increased by x%per week over 2 successive weeks. If at the begining, 2 Kgs were available for Rs 80 and after 2 weeks they were available for Rs 105.80, what is the value of x?

• by using compound interest :-
  P=80, A=105.80 n=2 r=??
  105.80=80*((1+r/100)^2)
  r=15% Ans
  
  
• 9 years agoHelpfull: Yes(28) No(0)
• 1st week
  1 kg = 40
  40 x% = 40+ (40*x)/100 = 40 {1+(x/100)}
  
  2nd week
  again 40%
  => 40 { 1+ (x/100)}^2 = 105.8/2 = 52.9
  => 1+(x/100) = 1.15
  => x = 15
  so the increasing rate per week is 15%
• 9 years agoHelpfull: Yes(22) No(1)
• ans is 15%
  let y is the percentage at which the price increased weekly
  (80*(y)/100)*y/100=105.80
  by solving you get y=115
  so increased percentage is 115-100=15
• 9 years agoHelpfull: Yes(5) No(0)
• x=16.12%
  per week increased amount per kg=((105.80/2)-(80/2))/2=6.45
  x=(6.45/40)*100
  =16.12%
  
• 9 years agoHelpfull: Yes(4) No(3)
• 15% is the solution
  solving 40*x/100 + 40
  and next week 40(x/100 + 1)^2=105.8/2
  on solving 15%
• 9 years agoHelpfull: Yes(2) No(0)
• ans is 15
  
  
  
  
• 9 years agoHelpfull: Yes(1) No(0)
• Answer is 15......
  Agree with Bhaskar
• 9 years agoHelpfull: Yes(1) No(1)
• 15% let go by answer and solve it
• 9 years agoHelpfull: Yes(1) No(0)
• y=40
  y+2x=52.9
  thus, x=6.45
  
• 9 years agoHelpfull: Yes(1) No(4)
• ans= 15%
  80*(1+x/100)^2 = 105.80
  x= 15%
• 9 years agoHelpfull: Yes(1) No(0)