First, turn this mixed number into an improper fraction.
1 11/16 becomes 27/16, because you're adding 16/16 to 11/16
Now, you divide 27 by 16 to find a decimal.
1.6875
To find the percentage, you multiply by 100, which is the same as moving the decimal place two spots to the right.
1.6875 becomes 168.75%
Therefore, 1 11/16 = 168.75%