$\"\"$

The expression is $\"\"$ .

Round to the nearest whole number then multiply.

21789 rounded to the nearest whole number is 20000.

89 rounded to the nearest whole number is 100.

$\"\"$

The expression becomes: $\"\"$

$\"\"$ (Divide: $\"\"$ )

So, $\"\"$

$\"\"$

The product is about $\"\"$ .