Question

given the following data, find the weight that represents the 39th percentile. weights of newborn babies 7.3 7.4 7.9 7.4 5.4 7.4 9.5 9.2 7.1 7.1 6.5 6.0 6.7 7.8 9.1

Explanation:

Step1: Arrange data in ascending order

$6.0,6.5,6.7,7.1,7.1,7.3,7.4,7.4,7.4,7.8,7.9,9.1,9.2,9.5$

Step2: Use percentile formula

The formula for the $p$ - th percentile of a data - set with $n$ values is $L=(p/100)\times n$. Here, $p = 39$ and $n = 14$. So, $L=(39/100)\times14=5.46$.

Step3: Determine the position

Since $L$ is not an integer, we round up to the next whole number. So the position is $6$.

Step4: Find the value

The $6$ - th value in the ordered data - set is $7.3$.

Answer:

$7.3$