not what it says on the box

I'm clearly not thinking straight despite 11 hours sleep. Counting has not gone well today.
I have some kids 100 piece jigsaws that have been grown out of but didn't want to give them away incomplete. A quick count of the first box revealed 104 pieces ( second more careful count did too) so I completed it so I could remove the spares, but all 104 pieces were used. I'm tempted to write "approx" on the box.
Another 100 piece needed all its 108, and the third I didn't even count but just did it anyway. The great news is 2 pieces were missing but I had them stashed from a previous tidy. So I can give them away safe in the knowledge that they are whole.