Dany bought a total of 20 games cards some of which cost $.25 each.and some of which cost $ .15 each.if dany spent $4.2 to buy these cards how many cards of each type did buy.

• let no. of cards be x & y
  
  x + y = 20 ---(1)
  
  .25x + .15y = 4.2 ----(2)
  => 25x + 15y = 420
  
  solving, x = 12 , y = 8
• 9 years agoHelpfull: Yes(17) No(2)
• let number of cards be x and (20-x)
  
  x*0.25+(20-x)*0.15=4.2
  
  solving,x=12 and 20-x =8
  then two numbers are 12 and 8
• 9 years agoHelpfull: Yes(2) No(0)
• let m be no of cards of $0.25, let n be the no of cards of $0.15,
  so, given m+n=20
  m(0.25)+n(0.15)=4.2
  i.e m(1/4)+n(3/20)=42/10
  5m+3n=84
  2m+3(20)=84 since m+n =20
  so m=12, n=8
• 9 years agoHelpfull: Yes(0) No(0)