Ana downloaded pictures. Each picture had a file size of 2.4 megabytes. What is the total file size in megabytes of 6 of these pictures?

The total file size of 6 pictures is 2.4 x 6 = <<2.4*6=14.4>>14.4 megabytes. Answer: \boxed{14.4}.

To find the total file size in megabytes of 6 pictures, you need to multiply the file size of each picture by the number of pictures.

File size of each picture = 2.4 megabytes
Number of pictures = 6

Total file size = File size of each picture × Number of pictures
= 2.4 megabytes × 6
= 14.4 megabytes

Therefore, the total file size in megabytes of 6 pictures is 14.4 megabytes.