To find the percentage change in the price of a product that is first decreased by 15% and then increased by 12%, we can follow these steps:

1. Let the original price be $P$.
2. The price after a 15% decrease: $P_{\text{new1}} = P \times (1 - 0.15) = 0.85P$
3. The price after a 12% increase on the new price: $P_{\text{new2}} = 0.85P \times (1 + 0.12) = 0.85P \times 1.12$
4. Simplifying this: $P_{\text{new2}} = 0.85 \times 1.12 \times P = 0.952P$
5. The final price is 0.952 times the original price $P$.

To find the overall percentage change: $\text{Percentage Change} = \left(\frac{P_{\text{new2}} - P}{P}\right) \times 100$ $= \left(\frac{0.952P - P}{P}\right) \times 100$ $= (0.952 - 1) \times 100$ [ = -0.048 \times 100