Let N = 553+ 173- 723. N is divisible by
A.Both 7 and 13
B.Both 3 and 13
C.Both 17 and 7
D.Both 3 and 17

• N = 553+ 173- 723 = 3
  which is divisible by 3 only.
• 10 years agoHelpfull: Yes(4) No(2)
• I think Question is 55^3+17^3-72^3
  Ans: 3 and 17
  Soln:
  55^3+17^3-72^3 CAN BE WRRITEN AS ((55+17)(55^2-55*17+17^2))-72^3 //use a^3+b^3 formula
  ((72)(55^2-55*17+17^2))-72^3)
  72(55^2-55*17+17^2-72^2) //Taking 72 as common
  72((55+72)(55-72)-55*17 +17^2)
  72((128)(-17)-55*17 +17^2)
  72*17( 128- 55*17 +17^1) //Taking 17 as common
  Now 17 and 72 Will be divisible by 17 and 3
  Thus solved
  
• 10 years agoHelpfull: Yes(4) No(0)
• I think Question is 55^3+17^3-72^3
  Ans: 3 and 17
  Soln:
  55^3+17^3-72^3 CAN BE WRRITEN AS ((55+17)(55^2-55*17+17^2))-72^3 //use a^3+b^3 formula
  ((72)(55^2-55*17+17^2))-72^3)
  72((55^2-55*17+17^2)-72^2) //
  
• 10 years agoHelpfull: Yes(0) No(0)