A $5\%$ leftover of half of the sandwiches will mean $5\%$ of $6$ varieties which is also equivalent to $10\%$ of $3$ varieties. This means that even if there is a $10\%$ additional sale of $2$ varieties there is still a loss of $10\%$ of $1$ variety. The current format helps to exactly match the demand and avoid any losses due to leftovers. This means that the new format benefits the shop by revenue of $5\%$ of $6$ varieties and cost saving of $10\%$ of $1$ variety.

An ERP helps in many ways to manage inventory in a system. It helps to forecast the demand based upon the historical trends and accordingly ensure that there is adequate inventory in the system to meet this demand. It also helps to schedule raw material delivery because freshness is a value add for the sandwich shop. The ERP will also help to keep a check on the costs and regularize the purchase cycle which can help Ajax with supplier discounts.

The store can also keep a track of the inventory from purchase to sales and ensure that there is no excess raw material which may lead to wastage. It is also a good system to manage data and information in a more structured manner.