Here's my solution... Might not be the cleanest (passing the whole array) but it sure looks pretty...

($\,$,)=("\n","\t");

@a=(1..15);

print "Before:",@a;
print "Selection:",picksome(5,@a);
print "After:",@a;

sub picksome { map { splice @_, rand @_, 1 } (1..shift) }
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