Bunuel wrote:
If s is an integer between 0 and 10, is t less than the average (arithmetic mean) of s and 10?
----0--s---(average)---10--- The average of s and 10 is halfway between s and 10.
The question asks whether t is in green area.
(1) t is closer to 10 on the number line than it is to s --> t is not in the green area. So, the answer to the question is NO. Sufficient.
(2) t is 5 times as large as s. If s=1 and t=5, then the answer is YES but if s=2 and t=10, then the answer is NO. Not sufficient.
Answer:
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