In the sequence 2 P E % 7 R A 4 # M 9 U T & 3 B I 6 K $ 5 N, how many elements lie between the second symbol counted from the left end and the second digit counted from the right end?

The symbols are %, #, & and $ at places 4, 9, 14 and 20, so the second from the left is # at place 9. The digits from the right end are 5 at place 21, then 6 at place 18, so the second from the right is 6 at place 18. Between places 9 and 18 lie places 10 to 17 — the eight elements M, 9, U, T, &, 3, B and I. Counting one of the two named elements as well gives 9 and counting both gives 10; taking 5 at place 21 for the second digit from the right, when it is in fact the first, stretches the count to 11.