There are 4 boxes colored red, yellow, green and blue. If 2 boxes are selected,
how many combinations are therefor at least one green box or one red box to
be selected?

• u take red ball... (red,yellow)(red,green)(red,blue)... and green take (red,green)(green,yellow)(green,blue),, but (green,red)or (red,green) take 2 time... so 6-1=5.....
• 12 years agoHelpfull: Yes(9) No(0)
• ((4c1+4c2)*2c1)/4c2=5
  answer
• 12 years agoHelpfull: Yes(2) No(1)
• 2C1*2C1+2C2=5
• 12 years agoHelpfull: Yes(0) No(2)