Only after this discussion, let them try the problem again. If they still get it wrong, then show them the correct answer from the key and explain the solution.
Some workbooks come with QR codes. Check the first few pages of your Turbo Math book. If there is a QR code or a link to a "Akıllı Tahta" (Smart Board) application, you can often view the solved pages there. Turbo Matematik 3. Sinif 1. Kitap Cevaplari