Answer:
1/4 of the cake.
Step-by-step explanation:
Since he ate 1/3 of 3/4 of the chocolate cake, we will need to multiply fractions to solve this.
[tex]\frac{3}{4} * \frac{1}{3} = \frac{3}{12} = \frac{1}{4}[/tex]
Therefore, he ate 1/4 of the entire cake.