Portfolio requirement - number of pieces?

Hi I’m applying for grad school (3 industrial design programs) this year and I have a question about portfolio requirements.

When it says “submit 7-10 samples of your work”

Does that mean 7-10 slides/images 7-10 projects with a few images each?

Also, same question for this one,

“submit 20 pieces that demonstrate your work”

20 slides/images or projects?


Should email/call to ask. Can’t be sure. When I applied to schools I applied as a graphic designer so each piece was basically one image.