Use following way :
NSMutableArray *first = [[NSMutableArray alloc] initWithObjects:@"1",@"2",@"3",@"4",@"5",@"6",@"7",@"8",@"9",@"10", nil];
NSMutableArray *sec = [[NSMutableArray alloc] init];
for(int i=5; i< [first count]; i++) {
[sec addObject:[first objectAtIndex:i]];
}
NSLog(@"sec - %@",sec);