Description of the game from Spielbox:

Reiner Knizia, himself a mathematician, has developed a new game in the “Clevermacher” series that will engage even notorious mathphobes: Primo Calculino. The ‘hero’ in this lovingly-produced game is the seller Johann, who has lots of tasty things for sale. Ready for the big sales, Johann, represented in the game as a seven cm high wooden figure, has not only the appropriate shopping tiles but also shopping bags in different sizes. And unfortunately, not everything fits into them! Little math artists will have to figure out more than just adding one plus one to make sure that only those things that belong land in the bags. The rest just wouldn’t fit…

Primo Calculino doesn’t just add enjoyment, it also subtracts and multiplies it. And so, while playing, mathematical abilities as well as memory and concentration are built. The nice thing is that nobody outside of adults will notice…

Here is a description of the game from Selecta Spielzeug:

A mathematical learning game with many variations.

You can put so many tasty things into your bag, but sometimes, they don´t all fit! This game will teach little mathematical wizards more than just adding up one and one.

Contents:
1 figure, 36 task cards, 40 food cards (2½ x 2½ in.), instructions

http://www.ludorium.at/SPIELE/selecta/primo_calculino_e0.htm
"Primo Calculino is played with different cards depending on age and knowledge level of the players, the coloured frames of the cards show the level of difficulty. 40 small cards show food stuff, Jonathan the vendor goes from player to player with an open card. Players try to turn up food that matches the number on Johanns card. To reach that number a player adds the value of the cards, in variants for older players they may add, subtract and multiply the numbers. If the number is reached, the player receives the card and can try to match the value of the next card. If it is not possible Johann goes to next player. The player with the most cards at the end of the game wins.

Educational game * Series: Clevermacher Lernspiel * 2-4 players from ages 5 to 9 * ca. 10 minutes * Designer: Reiner Knizia * Illustration: Barbara Kinzebach * 3066, Selecta, Germany, 2006 *** Selecta Spielzeug GmbH * www.selecta-spielzeug.de * info@selecta-spielzeug.de"