Which number should replace both the asterisks in (* /18) x (*/72) = 1 ?	Choices: A) 24 B) 30 C) 36 D) 42 E) 48

Rationale: "let ( y / 18 ) x ( y / 72 ) = 1 y ^ 2 = 18 x 72 = 18 x 18 x 4 y = ( 18 x 2 ) = 36 the answer is c ."
Answer: C