The greatest place is the leftmost place. In 25.691, 2 is the greatest place and it is in the tens place. So, to round it to the nearest tens place, look at the number to the right of 2. Since that number is 5, change the 2 to 3. Then, change all numbers except for the 2 to 0, making it 30.000. You can also write 30 and ignore the zeros to the right of the decimal.