Shoe Shine is a local retail shoe store located on the north side of Centerville. Annual demand for a popular sandal is 500 pairs, and John Dirk, the owner of Shoe Shine, has been in the habit of ordering 100 pairs at a time. John estimates that the ordering cost is $10 per order. The cost of the sandal is $5 per pair.

If the carry cost were 10% of the cost, then the optimal order quantity would be_______________ pairs of sandal. (Please round to an integer and include no units.)

If the optimal order quantity were 100 pairs of sandal, the carry cost should be ________________ percent of the cost. (Please round to a whole percentage.)