Question

The value of \[\sqrt {0.9} \] is (approx.):
A). \[0.3\]
B). \[0.6\]
C). \[0.9\]
D). \[0.4\]

Answer 1

Hint: In the given question, we have been given a number inside the square root bracket which is not a perfect square; its approximate value is to be found. We are going to solve it by finding the option which is closest to the given number. For that, we must have the basics about the square and square roots cleared. Then, we are just going to use the formula, apply its result and find the answer.

Formula used:
We are going to use the formula of square and square root:
\[\sqrt {{x^2}} = x\]

Complete step by step solution:
We have to find the approximate value of \[\sqrt {0.9} \].
The given four options are: \[0.3\], \[0.6\], \[0.9\] and \[0.4\].
Let us find the square of the four numbers:
\[{\left( {0.3} \right)^2} = 0.09\]
\[{\left( {0.6} \right)^2} = 0.36\]
\[{\left( {0.9} \right)^2} = 0.81\]
\[{\left( {0.4} \right)^2} = 0.16\]
Hence, the closest one is \[\left( {0.9} \right)\].
Thus the correct option is C.

Note: In the given question, we had to find the approximate value of a number inside the square root bracket which was not a perfect square. We solved it by choosing the option closest to the given number. So, it showed that if we have the basic knowledge of the given subject of square and square root, we can easily find the answer to any complex problem.