A data set has 60 observations with minimum value equal to 30 and a maximum value equal to 72. The estimated class width using the 2k>n rule to determine the number of classes is ___.

7

Explanation:

class width = (largest value-smallest value) / k

where k is the number of classes.

According to 2^k>n rule

We choose different value of k till we get the 2^k greater than number of observation.

The given value of n=60

Now,

2^1=2 <60

2^2=4 <60

2^3=8 <60

2^4=16 <60

2^5=32 <60

2^6=64 >60

So, k=6.

Now class width = (largest value-smallest value) / k

class width=72-30/6

class width=42/6=7

class width=7