If a sum of money compound annually amounts of thrice itself in 3 years. In how many years will it become 9 times itself.
(a) 6 (b) 8 (c) 10 (d) 12

• let the amount be A
  for 3 years it becomes 3A
  so, for 6 years it becomes 3(3A)=9A
  hence the answer is option a)6
• 12 years agoHelpfull: Yes(36) No(13)
• ci=p(1+r/100)^t
  given
  3p=p(1+r/100)^3
  now (1+r/100)^3=3
  now squaring on both sides
  (1+r/100)^3*2=3^2
  (1+r/100)^6=9
  hence answer is 6 years
• 9 years agoHelpfull: Yes(12) No(1)
• let, initial amount be 100 rs
  it get triples in 3 years ie. we are getting 300 rs in 3 years
  so intrest is 300-100=200 Rs
  
  now when it become 9 times we will get intrest =900-100=800Rs
  
  We get,
  3 YEARS==200
  ? YEARS==800
  
  ?=(800*3)/200=12 YEARS
  AND THIS IS 100 % CORRECT SOLUTION
• 9 years agoHelpfull: Yes(1) No(15)
• bbrihvihivhihhi
• 9 years agoHelpfull: Yes(0) No(13)
• let principle=x in 3 years it became 3x
  3x=x(1+(r/100))^3==> 3=(1+(r/100))^3------------------> I
  
  9x=x(1+(r/100))^n
  
  9=(1+(r/100))^n write 9= 3^2
  ==> 3^2=(1+(r/100))^n sub equ I here
  ((1+(r/100))^3)^2=(1+(r/100))^n
  
  
  1+(r/100))^6=(1+(r/100))^n
  
  
  so n=6.
• 8 years agoHelpfull: Yes(0) No(0)