The bug will be
inches long once it is enlarged for the movie.
Step-by-step explanation
In a horror movie ,bugs were enlarged on a scale of 1 : 325 . That means, the ratio of the original size to the enlarged size is 1 : 325
Original length of the bug is
inches or 1.5 inches
Suppose, the enlarged length of the bug is
inches.
Now, according to the ratio.......

So, the bug will be
inches long once it is enlarged for the movie.