W,X,Y,Z are integers. The expression X - Y - Z is even and the expression Y - Z - W is odd. If X is even what must be true.
option
A) W must be odd.
B) Y - Z must be odd.
C) Z must be even.
D) Z must be odd.

• w must be odd
• 11 years agoHelpfull: Yes(17) No(2)
• even-even=even=>Y-Z must be even [since x is even]
  even-odd=odd=>w must be odd
• 11 years agoHelpfull: Yes(6) No(1)
• W must be odd
  
• 8 years agoHelpfull: Yes(1) No(0)
• assume x=6,y=3,z=2,w=1
  substitute satisfying the conditions so as a result we will get answer only if w is add so w must be odd
• 11 years agoHelpfull: Yes(0) No(4)
• w must be odd since x is even then y-z must be even => w -x-z to be odd w must be odd
• 11 years agoHelpfull: Yes(0) No(0)
• w must be odd
• 11 years agoHelpfull: Yes(0) No(0)
• X-Y-Z= even
  =>X-(Y+Z)= even
  X=even
  as, odd+odd=even
  so z must be odd
  
• 9 years agoHelpfull: Yes(0) No(0)
• A) W must be odd
• 8 years agoHelpfull: Yes(0) No(0)
• A. Adding the two expressions we get X-2Z-W= even + odd= odd. Since X and 2Z are even , w must be odd
  to get an odd result.
• 8 years agoHelpfull: Yes(0) No(0)
• assume x=6,y=3,z=2,w=1
  substitute satisfying the conditions so as a result we will get answer only if w is add so w must be odd
• 8 years agoHelpfull: Yes(0) No(0)