Each term's initial letter position in the alphabet:

1 >> One >> O >> 15th letter.
.
.
4 >> Four >> F >> 6th letter.
.
.
.
20 >> Ten >> T >> 20th letter.

Puzzle 1518

Find an anagram of INSATIABLE.

[Ref: ZNSQ]

Hint:

Answer: BANALITIES.

Puzzle 1519

I once cashed a cheque at the bank. I had spent £20.68 before I realised the bank clerk had made a mistake. He had transposed the pounds with the pence. I now had exactly 9 times the value of the original cheque. What was the original cheque's value?