Question

The boiling point of water is 212°F at sea level. Andres lives at an elevation of

7500 ft and finds that water boils at 198°F, What is the percent decrease in
the boiling point of water from sea level to 7,500 ft? Give your answer to the
nearest tenth of a percent. Show your work.

Answer 1

6.6% decrease

Explanation:

You want to know the percent decrease in the boiling point of water if it decreases from 212 °F to 198 °F.

Percent change

The percent change between two values can be found from ...

percent change = ((new value)/(old value) -1) × 100%

percent change = (198/212 -1) × 100% ≈ -6.6%

The decrease in the boiling point is about 6.6%.

__

Additional comment

Finding the change between the given numbers is shown above. However, in terms of boiling point, this is a meaningless calculation. A percent change is only a useful calculation when measurements are on a ratio scale, one with a true zero.

For the percentage change in boiling point temperature to be meaninful, we need to express the temperatures on the Rankin (or Kelvin) scale, with respect to absolute zero. On the Rankin scale, the change would be from 671.67 to 657.67, a change of about -2.1%.

<95141404393>