The students of a Vidyalaya were asked to participate in a competition for making and decorating penholders in the shape of a cylinder with a base, using cardboard. Each penholder was to be of radius 3 cm and height 10.5 cm. The Vidyalaya was to supply the competitors with cardboard. If there were 35 competitors, how much cardboard was required to be bought for the competition?

Explanation

To find out how much cardboard is required for the competition, we need to calculate the surface area of a single cylindrical penholder and then multiply that by the number of competitors.

### Step-by-Step Solution:

1. **Identify the dimensions of the cylinder:**
- Radius (r) = 3 cm
- Height (h) = 10.5 cm

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