# Square and Cube Roots Quiz Set 019

### Question 1

What is the value of \${√625/2}\$ × \${2/√25}\$ × \${2/√4}\$?

A

5.

B

5√5.

C

√5;.

D

1/√5.

Soln.
Ans: a

The given expression can be simplified to \${√5^4/2}\$ × \${2/√5^2}\$ × \${2/√2^2}\$, which is same as \${5^2/2}\$ × \${2/5}\$ × \${2/2}\$, which cancels to 5.

### Question 2

How many 3 digit numbers are their whose squares end in 8?

A

0.

B

4.

C

9.

D

16.

Soln.
Ans: a

It is not possible for the square of any number to end in 2, 3, 7 or 8. Hence the answer is 0.

### Question 3

What is the least number that should be subtracted from 0.0281 to make it a perfect square?

A

0.02.

B

0.3.

C

0.2.

D

0.03.

Soln.
Ans: a

We know that 0.09 = \$√0.0081\$, so by inspection we can see that 0.0281 - 0.02 will give us 0.0081.

### Question 4

What is the value of \${√1296/6}\$ × \${4/√36}\$ × \${6/√16}\$?

A

6.

B

4.

C

1.414.

D

16.

Soln.
Ans: a

The given expression can be simplified to \${√6^4/6}\$ × \${4/√6^2}\$ × \${6/√4^2}\$, which is same as \${6^2/6}\$ × \${4/6}\$ × \${6/4}\$, which cancels to 6.

### Question 5

What is the value of \${√17}/2\$ − \$3/{√17}\$?

A

\${11√17}/34\$.

B

\${21√17}/34\$.

C

\${22√17}/34\$.

D

\${20√17}/34\$.

Soln.
Ans: a

The given expression can be simplified to \${{(√17)^2} - 2 × 3}/{2 × √17}\$, which is same as \${17 - 6}/{2 × √17}\$, which is same as \${11/{2 × √17}\$. Rationalizing, we get \${11/{2 × √17} × {√17/√17}\$ which gives \${11√17}/34\$ 