How to select the split point for Continuous Attribute Age
For 35 split, there is an error in the denominator. It should be 5 as the total number of items for D&lt;35 is 5

D&lt;35 =&gt; [2+, 3-], Entropy (D&lt;35) = -[2/5 x $log_2$(2/5) + 3/5 x $log_2$⁡(3/5)]