blueseas wrote:
Asifpirlo wrote:
How many numbers of this sequence of 342 numbers are odd?
(1) The sequence starts with -1,3,-3,..........
(2) Except for the 1st two numbers, every number in the sequence is the product of the two immediately preceding numbers
(1) The sequence starts with -1,3,-3,..........
(2) Except for the 1st two numbers, every number in the sequence is the product of the two immediately preceding numbers
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statement 1:The sequence starts with -1,3,-3,..........
insufficient as we dont know what all numbers are there in this series.
statement 2:Except for the 1st two numbers, every number in the sequence is the product of the two immediately preceding numbers
insufficient as we dont know what are numbers in the series.
combining:
first two numbers are -1,3...now the following numbers will be multiple of previous 2 numbers ...
you can see both numbers are ODD....and we knowODD*ODD = ODD..So clearly following digits will be ODD.
Hence we can conclude that all numbers are odd
hence sufficient.
C
yes thats it, perfect solution. All the 342 numbers are odd