Ordering the scores they have got in their 5 basketball games:
60, 63, 65, 65, and 67
There are 5 values, and odd number, then the median score is the central value, that means number 3: Median score=65
If they only score 30 points in their next game, the scores would be:
30, 60, 63, 65, 65, and 67
6 values, an even number, then the median score is the average of the two central values :
Median score=(63+65)/2=(128)/2→Median score=64
Answer: Their median score will decrease 1 point (64-65=-1)