State the formula

The curved surface area (CSA) of a cylinder is given by $CSA = 2 \pi r h$, where $r$ is the radius and $h$ is the height.

$CSA = 2 \times \pi \times r \times h$

Substitute given values

Substitute $CSA = 4500$, $h = 39$, and $\pi = 22/7$ into the formula: $4500 = 2 \times (22/7) \times r \times 39$.

$4500 = 2 \times \frac{22}{7} \times r \times 39$

Solve for r

Isolate $r$: $r = \frac{4500 \times 7}{2 \times 22 \times 39} = \frac{31500}{1716}$.

$r = \frac{31500}{1716} \approx 18.3566$

Round to two decimal places

Rounding $18.3566$ to two decimal places gives $18.36$.

$r \approx 18.36$