Let's begin by identifying key information given to us:
You told your friend you could eat 2/3 of a large pizza
However, you ate 2/5 of what you said
The fraction of pizza you ate is given by the product of 2/3 & 2/5. We have it thus:
[tex]\begin{gathered} =\frac{2}{3}\times\frac{2}{5} \\ =\frac{2\times2}{3\times5} \\ =\frac{4}{15} \end{gathered}[/tex]Therefore, you ate 4/15 of the pizza