text: ## If $$r$$ and $$s$$ are positive integers, is $$r + s$$ even?
  
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  ### If $$r$$ and $$s$$ are positive integers, is $$r + s$$ even?
  
  by Vincen » Wed Feb 23, 2022 4:00 am
  
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  ## Global Stats
  
  If $$r$$ and $$s$$ are positive integers, is $$r + s$$ even?
  
  (1) $$r$$ is even.
  (2) $$s$$ is even.
  
  Source: Official Guide
  
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  ### Re: If $$r$$ and $$s$$ are positive integers, is $$r + s$$ even?
  
  by Brent@GMATPrepNow » Thu Feb 24, 2022 8:06 am
  
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  A
  
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  C
  
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  ## Global Stats
  
  Vincen wrote:
  Wed Feb 23, 2022 4:00 am
  If $$r$$ and $$s$$ are positive integers, is $$r + s$$ even?
  
  (1) $$r$$ is even.
  (2) $$s$$ is even.
  
  Source: Official Guide
  Given: r and s are positive integers
  
  Target question: Is r + s even?
  
  Statement 1: r is even.
  Since we have no information about s, we cannot determine whether r + s is even
  Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT
  
  Statement 2: s is even
  Since we have no information about r, we cannot determine whether r + s is even
  Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT
  
  Statements 1 and 2 combined
  Statement 1 tells us that r is EVEN
  Statement 2 tells us that s is EVEN
  Since EVEN + EVEN = EVEN, we know that r + s is EVEN
  Since we can answer the target question with certainty, the combined statements are SUFFICIENT