1. **State the problem:** Calculate the aftersale and refund rate for each store. 2. **Define terms:** - Refund Amount: Total money refunded for a store. - NMV (Net Merchandise Value): Total sales value for a store. - Refund Rate = \( \frac{\text{Sum of Refund Amount}}{\text{NMV}} \times 100\% \) 3. **Calculate refund rate for each store:** - Store 1169: Refund Rate = \( \frac{1169}{2978} \times 100 = 39.24\% \) - Store 5242: Refund Rate = \( \frac{5242}{21832} \times 100 = 24.00\% \) - Store 1558: Refund Rate = \( \frac{1558}{25173} \times 100 = 6.19\% \) - Store 5109: Refund Rate = \( \frac{5109}{4578} \times 100 = 111.56\% \) - Store 5615: Refund Rate = \( \frac{5615}{9348} \times 100 = 60.08\% \) - Store 462: Refund Rate = \( \frac{462}{5629} \times 100 = 8.21\% \) - Store 2955: Refund Rate = \( \frac{2955}{58517} \times 100 = 5.05\% \) - Store 724: Refund Rate = \( \frac{724}{0} \) (undefined, NMV is zero) - Store 2138: Refund Rate = \( \frac{2138}{39653} \times 100 = 5.39\% \) 4. **Interpretation:** Refund rate shows the percentage of sales refunded. A rate over 100% (Store 5109) suggests refund amount exceeds sales, possibly data inconsistency. **Final answers:** - Store 1169: 39.24% - Store 5242: 24.00% - Store 1558: 6.19% - Store 5109: 111.56% - Store 5615: 60.08% - Store 462: 8.21% - Store 2955: 5.05% - Store 724: Undefined (NMV=0) - Store 2138: 5.39%