To determine how many platters the baker needs to display 64 cookies, we first find out how many cookies are displayed on each platter when there are 144 cookies on 9 platters.
We can calculate the number of cookies per platter by dividing the total number of cookies by the number of platters:
\[ \text{Cookies per platter} = \frac{144 \text{ cookies}}{9 \text{ platters}} = 16 \text{ cookies per platter} \]
Now, we want to find out how many platters are needed to display 64 cookies. To do this, we divide the total number of cookies (64) by the number of cookies per platter (16):
\[ \text{Number of platters} = \frac{64 \text{ cookies}}{16 \text{ cookies per platter}} = 4 \text{ platters} \]
Thus, the baker needs 4 platters to display 64 cookies.