The population of mice in a market doubles every day. Every day 20 mice are killed.
How many mice are there if after every three days, the number of mice becomes same
again?

• consider x number of mice
  1st day - x
  2nd day - (2x-20)
  3rd day - [2(2x-20)-20]
  after third day the value becomes equal to the first day so (4x-40-20)=x
  solve for x
  x=20
• 6 years agoHelpfull: Yes(8) No(1)
• day1: population of mice=2x-20
  day 2:2(2x-20)-20=4x-60
  day 3:2(4x-60)-20=x
  =>8x-140=x
  =>x=20
• 6 years agoHelpfull: Yes(2) No(0)
• 20
  let on the first day =x
  2 nd day =2x-20
  3rd day =2(2x-20)-20
  = 4x-40-20
  =4x-60
  and it is given that after 3 day the population is same as 1st day hus
  equating both sides we get :
  x=4x-60
  3x=60
  x=20
• 6 years agoHelpfull: Yes(1) No(0)