Suppose a psychrometer reads 80°F for the dry bulb and 76°F for the wet bulb. What is the relative humidity?

84%

Explanation:

Using the table attached, one can find out the Relative humidity.

Look at the intersection between the temperature on the dry bulb and the difference between the temperature on the dry and wet bulb.

Dry bulb temperature = 80°F

Wet bulb temperature = 76°F

Difference = 80 - 76 = 4°F

Relative humidity is therefore:

= 84%

there are two significant figures.