The answer is 1988 cm².

The method:

1. First, find the rectangular table area.

We will add the length and the wide of cloth by (7 cm × 2) = 14 cm.

So, we got (78 cm + 14 cm = 92 cm) and (50 cm + 14 cm = 64 cm)

After that, multiply the length and the wide of rectangular table.

Area of table = 92 cm × 64 cm = 5888 cm²

2. Second, find the area of cloth.

Multiply the length and the wide of cloth.

Area of the cloth = 78 cm × 50 cm = 3900 cm²

3. Then, find the area of table not covered by cloth by subtract the area of rectangular table and the area of cloth.

Area = 5888 cm² - 3900 cm² = 1988 cm²

So, the area of table not covered by cloth is 1988 cm².