Question

A set contains these numbers: 6, 11, 15, 18, 23, 28, 34, 37, 41, 45.
What is the value of the 60th percentile (P₆₀)?

Options

• 23

• 28

• 31.2

• 34

Answer 1

31.2

Explanation: 

Apply P₆₀ = size of 60(n+1)/100th observation. Here, n=10.
= 60 × 11/100 = 6.6th observation.
Interpolate between 6th (28) and 7th (34): P₆₀=28+0.6×(34−28)=28+3.6=31.6 (closest to option C).