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I have two questions that I need help with:

1) How many single digit even natural number solutions are there for the equation $A+B+C+D = 24$ such that $A+B > C+D$

A)20 B)11 C)16 D)24

2) Three positive real numbers $x,y,z$ are such that $x+y+Z = 1$. which of the following inequalities best discribe the relation between $XY,YZ,ZX$.

A) $xy+yz+zx > 1/3$

B) $xy+yz+zx <1/3$

C) $xy+yz+zx \le 1/3$

D) $xy+yz+zx \le 2/3$

  • 1
    For the first, do you count $0$ as a natural? Some do, some don't. For the second, please make sure the variables are consistently capitals or lower case.2012-06-25

3 Answers 3