Question

The average ambient temperatures (in degree Celsius) for a region for 15 years from 2001-2015 is given below.

26.3, 29.7, 31, 29.8, 26.8, 27.6, 27.4, 27.0, 27.6, 27.8, 30.0, 32.0, 28.9, 30.5, 29.5

Find the temperature corresponding to the 80th percentile.

• A. 27.8
• B. 28.8
• C. 29.6
• D. 30.4

Answer 1

The correct option is D

30.4

Arrange the observations in ascending
order.

26.3, 26.8, 27.0, 27.4, 27.6, 27.6, 27.8,
28.9, 29.5, 29.7, 29.8, 30, 30.5, 31, 32

Here, N=15
$80thpercentile,P_{80}=sizeof80\left(\frac{N+1}{100}\right)thobservation=sizeof12.8thobservation$

Here, the 12th observation is 30 and
the 13th observation is 30.5
$\therefore P_{80}=30+0.8\times (30.5-30)=30+0.8\times .5=30.4$