Q. At what rate percent per annum will the simple interest on a sum of money be 2/5 of the amount in 10 years?

• if x is the amount and r is rate of interest, then
  x*2/5= x*r*10/100
  r= 4%
• 11 years agoHelpfull: Yes(2) No(0)
• let us assume p=1;
  t=10 years;
  r=?
  i=2/5;
  2/5=1*10*r/100------>r=4%....
• 11 years agoHelpfull: Yes(2) No(0)
• amt=x
  sum=2/5x
  amt=si+sum=>x=2/5x+si
  si=3x/5
  3x/5=2x/5*10*r/100
  r=15%
• 11 years agoHelpfull: Yes(1) No(1)
• From the Question:
  
  At what %, SI will be = 2/5 (Amount)
  
  SI = 2/5 A
  
  SI = 2/5 (SI + P)
  
  5*SI = 2*SI + 2*P
  
  3*SI =2*P
  
  3*(PNR/100) = 2*P
  
  3*(P*10*R/100) = 2*P
  
  cancel P on both sides and simplify
  
  3*(10*R/100) = 2
  
  So, RATE OF INTEREST is,
  
  R = 200/30
  
  R = 20/3 %
  
  R = 6 Two Third % or 6.66%
• 5 years agoHelpfull: Yes(1) No(0)
• 1/5=(1*R*10)/100
  so R=2%
• 11 years agoHelpfull: Yes(0) No(3)
• 2/5th is 40%
  so 40% interest in 10 yrs so Simple Interest per annum is 40/10=4%
  so 4% is answer
• 11 years agoHelpfull: Yes(0) No(1)