The Cz to Pz distance represents what fraction of the nasion-to-inion distance when that total distance is 36 cm and Cz-Pz is 7.2 cm?

The Cz to Pz distance represents what fraction of the nasion-to-inion distance when that total distance is 36 cm and Cz-Pz is 7.2 cm?

• A. 1/5
• B. 1/4
• C. 1/3
• D. 1/6

Answer: (A)

The concept here is treating Cz–Pz as a fraction of the full head length from nasion to inion. If that total distance is 36 cm and Cz–Pz is 7.2 cm, divide 7.2 by 36. Doing the math gives 0.2, which is 1/5. So Cz–Pz is one-fifth of the nasion–inion distance. Quick check: 1/4 of 36 is 9 cm, 1/6 is 6 cm, 1/3 is 12 cm, so 7.2 cm matches 1/5 (0.2 × 36 = 7.2).

The concept here is treating Cz–Pz as a fraction of the full head length from nasion to inion. If that total distance is 36 cm and Cz–Pz is 7.2 cm, divide 7.2 by 36. Doing the math gives 0.2, which is 1/5. So Cz–Pz is one-fifth of the nasion–inion distance. Quick check: 1/4 of 36 is 9 cm, 1/6 is 6 cm, 1/3 is 12 cm, so 7.2 cm matches 1/5 (0.2 × 36 = 7.2).