Summ of all numbers = 60 * 4 = 240
1) x , 51,L ==> L =190 - 51 = 139
51 & 139 add up to 190
Remaining 2 numbers must add up to = 240 - 190 = 50
Possible combinations
50 ------ 0 & 50 ... Not possible because it is given that numbers are positive & distinct integers
50 ----- 1 & 49
50 ----- 2 & 48.
Sufficient to answer the questions.
2) 2 middle term be x & y
Median = (x + y)/2 = 50.
x + y = 100
x & y are distinct ==> either of one is greater than 50 & other is less than 50.
==> Overall 2 terms less than 50 & 2 term greater than 50.
Sufficient.
Ans- D
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