simple interest on an amount at 4% per annum for 13 months is more than the simple interest on the same sum for 8 months at 6% per annum by rs 40. what is the principle amount

a.3600
b.12000
c.4800
d.24000

• P*4*13/100*12 -p*6*8/100*12=40
  
  after solving p=12000
  option B
• 10 years agoHelpfull: Yes(21) No(9)
• For Sajid specially who is asking why 12??
  as we know SI = P*R*T/100;
  to convert the given time into years (given in months)..13 months=1 year and one month
  so it is 1 1/12 =13/12:
  as it is given that
  P*4*13/100*12 - P*6*8/100*12=40:
  P=12000/ by solving.
  Hope Sajid Satisfied
  
• 9 years agoHelpfull: Yes(14) No(0)
• let the sum be Rs.x. SI= PRT/100; 4*13*x/100*12-x*6*8/100*12=40;
  x=12000
• 9 years agoHelpfull: Yes(3) No(0)
• 1yr = 12mnth
• 9 years agoHelpfull: Yes(2) No(1)
• why you are taking
  *12 can u tell me
  
• 9 years agoHelpfull: Yes(1) No(0)
• [(x*4*13)/100*12]-[(x*6*8)/100*12]=40
  x=12000
  
• 9 years agoHelpfull: Yes(1) No(0)
• (p*13*4)/(100*12) = (p*8*6)/(100*12)+40
  52p = 48p + 40*100*12
  4p = 40*100*12
  p = 12000
• 6 years agoHelpfull: Yes(0) No(0)