To find the diameter of the circle, we use the formula for the circumference of a circle:

$C = \pi d$

where:

• $C = 15$ cm (given circumference),
• $d$ is the diameter,
• $\pi \approx 3.1416$.

Rearranging the formula for $d$:

$d = \frac{C}{\pi} = \frac{15}{\pi}$

Using $\pi \approx 3.1416$:

$d \approx \frac{15}{3.1416} \approx 4.8 \text{ cm}$

So, the diameter to 1 decimal place is 4.8 cm.

Would you like a more detailed explanation?

Here are five related questions to expand your understanding:

1. How do you calculate the radius of a circle given its circumference?
2. What is the formula for the area of a circle, and how would you calculate it using the given circumference?
3. How does the value of $\pi$ affect calculations in circular geometry?
4. What are some real-world applications of circumference and diameter calculations?
5. How can you estimate $\pi$ using measurements from a physical circular object?

Tip: Always use the most accurate value of $\pi$ available in your calculator for precise results.