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alltimeacheiver
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as k is less than 17 and also k-1 is a square of an integer; therefore possible values of k would be; 1,2,5,10;alltimeacheiver wrote:ques If K is a integer less than 17 and k-1 is the square of an integer, what is value of k
1 k is an even integer Insufficeint
2 k+2 is the square of an ingteger
in second it can be two option if 2+2= 4 and 14+2= 16
So I marked e but the ans is but how. If something i missed
1) if k is an even integer than possible values of k would be 2,10 hence 1 is not sufficient to answer the question..!!!
2)k+2 is a square of an integer, now from the possible values of k as per the stem of the question(1,2,5,10) only 2 is the value which satisfies initial as well as the condition mentioned in statement..!!! (2-1=1 which is a perfect square and 2+2=4 which is a perfect square) therefore 2 alone is sufficient to answer the question..!!!
hence B
