zanaik89 wrote:
Bunuel wrote:
mehdiov wrote:
The positive integers r, s, and t are such that r is divisible by s and s is divisible by t. Is r even?
(1) st is odd.
(2) rt is even.
(1) st is odd.
(2) rt is even.
(1)\(st=odd\) , clearly not sufficient as no info about\(r\) , for example if\(r=6\) ,\(s=1\) and\(t=1\) then answer is YES but if\(r=3\) ,\(s=1\) and\(t=1\) then the answer is NO.
(2)\(rt=even\) . For product of 2 integers to be even either one or both must be even. Can\(r\) not to be even? The only chance would be if\(t\) is even and\(r\) is odd. Let's check if this scenario is possible: if\(t\) is
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