1. **State the problem:** Peter has 65 pinwheels divided equally into 10 jars. He gave away all but 1 jar and the leftover pinwheels. We need to find how many pinwheels he kept. 2. **Understand the division:** When dividing 65 pinwheels into 10 jars equally, some pinwheels may be leftover because 65 is not perfectly divisible by 10. 3. **Calculate pinwheels per jar:** Use integer division to find how many pinwheels are in each jar: $$\text{pinwheels per jar} = \left\lfloor \frac{65}{10} \right\rfloor = 6$$ 4. **Calculate leftover pinwheels:** Find the remainder when 65 is divided by 10: $$\text{leftover} = 65 - 10 \times 6 = 65 - 60 = 5$$ 5. **Calculate total pinwheels kept:** He kept 1 jar plus the leftover pinwheels: $$\text{kept} = 6 + 5 = 11$$ **Final answer:** Peter kept 11 pinwheels.