A B C D ARE FOUR TOWNS, ANY THREE OF WHICH ARE NON COLLINEAR.NUMBER OF WAYS TO CONSTRUCT THREE ROADS EACH JOINING A PAIR OF TOWN SO THAT ROADS DO NOT FORM A TRIANGLE IS:CAT 1995....DONT KNOW OA

1) 7
2) 8
3) 9
4) MORE THAN 9

• More than 9
  
  4 triangles are possible when 1 town is not connected.
  choosing 3 pairs out of 6 possible pairs = 6C3 = 20
  
  NUMBER OF WAYS TO CONSTRUCT THREE ROADS EACH JOINING A PAIR OF TOWN SO THAT ROADS DO NOT FORM A TRIANGLE = 20-4=16
• 11 years agoHelpfull: Yes(1) No(6)
• To construct 2 roads, three towns can be selected out of 4 in 4 x 3 x 2 = 24 ways. Now, if the third road goes from the third town to the first town, a triangle is formed and if it goes to the fourth town, a triangle is not formed. So there are 24 ways to form a triangle and 24 ways of avoiding a triangle.
• 8 years agoHelpfull: Yes(1) No(5)
• dont need to copy paste mr. Prakash
• 7 years agoHelpfull: Yes(1) No(1)