17 blocks.......

I have been sewing a few strips onto blocks now and then so last night I made an effort to get more blocks up to the 15.5" size.  I was going to make 24 blocks which would make a 60" x 90" quilt but now I'm thinking maybe 20 blocks for a 60" x 75" will be enough.  I'm thinking large lap quilt for this one.  I guess my layout will determine the number of blocks that it needs.  If I stay with this type layout, 20 will be enough.