Bluebulb Projects' The Measure of Things presents:
30 is about three-fifths the number of Teeth in a Great White Shark's Mouth.
In other words, it's 0.630 times the count of Teeth in a Great White Shark's Mouth, and the count of Teeth in a Great White Shark's Mouth is 1.60 times that amount.
(Carcharodon carcharias) (average; including developing rows)
A Great White Shark has 48 exposed teeth on their upper and lower jaws. Behind these exposed teeth are developing teeth — up to 300 in about 5 rows. The sharks will continuously lose and replace the exposed teeth throughout their lives.