Question

use the accompanying radiation levels (in $\frac{w}{kg}$) for 50 different cell - phones. find the percentile $p_{30}$. $p_{30}=square\frac{w}{kg}$ (type an integer or decimal rounded to two decimal places as needed).

Explanation:

Step1: Calculate index

The formula to find the index $i$ for the $p$ - th percentile is $i=\frac{p}{100}\times n$, where $p = 30$ and $n=50$. So $i=\frac{30}{100}\times50 = 15$.

Step2: Determine the percentile value

Since $i = 15$ is an integer, the $p$ - th percentile is the average of the value in the $i$ - th and $(i + 1)$ - th ordered positions. In the ordered data - set, the 15th value is $1.16$ and the 16th value is $1.20$. The average is $\frac{1.16+1.20}{2}=1.18$.

Answer:

$1.18$