Given that 100.48 = x, 100.70 = y and xz = y2, then the value of z is close to:  Pick one: A) 2.2 B) 8.2 C) 2.9 D) 2.1 E) 2.6

Rationale: "xz = y 2 10 ( 0.48 z ) = 10 ( 2 x 0.70 ) = 101.40 0.48 z = 1.40 z = 140 = 35 = 2.9 ( approx . ) 48 12 answer : c"
Answer: C