Need to batch process to reduce file size

[peter]

I have just tried to upload our holiday pictures to photobox to produce a book.
rejected most of them as the file size limit is 10mb. They are all raw edited in PS saved as jpeg but still too large. I have CS6 but not lightroom . What is the best way of doing this ? About 400 files to do.

thanks

 

[peter]

Looked at image processor in cs6 but no option of file size.

 

[peter]

Printing to an A3 size book I have done as John suggested and used lightroom to limit file size . Takes some down to 7mb though they look ok . File size is huge as they were from a D800, raw files converted to jpeg.
Thanks folks some of the files below