In Lhasa, Tibet, the elevation is 12,000 feet. The altimeter reading in an airplane is 19.50 in Hg. This pressure is equal to how many mm Hg?

• A. 660.4 mm Hg
• B. 495.3 mm Hg
• C. 740.0 mm Hg
• D. 1013.2 mm Hg

Answer: (B)

Verified step by step guidance

1. Understand that the problem requires converting pressure from inches of mercury (in Hg) to millimeters of mercury (mm Hg).
2. Recall the conversion factor between inches of mercury and millimeters of mercury: 1 in Hg is equal to 25.4 mm Hg.
3. Set up the conversion equation using the given pressure in inches of mercury: \( P_{mmHg} = P_{inHg} \times 25.4 \).
4. Substitute the given pressure value (19.50 in Hg) into the equation: \( P_{mmHg} = 19.50 \times 25.4 \).
5. Perform the multiplication to find the pressure in mm Hg, ensuring units are consistent throughout the calculation.