It is often useful to estimate the value of a square root to determine if your answer is reasonable.  

1. What would be a reasonable estimate of $\sqrt { 68 }$? Explain your thinking. After you have made an estimate, check your estimation with a calculator.

   Answer (a):

   $\sqrt{68}\cong8.2$ because $\sqrt{64}=8$, so $\sqrt{68}$ must be a little higher.

2. Repeat this process to estimate the values below.

   (1) $\sqrt { 5 }$  

   (2) $\sqrt { 85 }$  

   (3) $\sqrt { 50 }$ 

   (4) $\sqrt { 22 }$ 

   Answer (b2):

   Since square root of $81$ is $9$, then square root of $85$ is a little more $\approx9.2$.