The second option ! 2.54 - 2.3 = 0.24
Answer:

Step-by-step explanation:
Given



Required

This is calculated as:




<u><em>Answer:</em></u>
You should multiply the expression by 
<u><em>Explanation:</em></u>
To rationalize any expression, you must multiply it by its conjugate. A conjugate is defined as a similar expression to the original one but with an opposite sign
<u>This means that:</u>
The conjugate of a + b would be a - b
Now, the given expression is 
<u>Consider the denominator:</u>
From the above, we can conclude that the conjugate of
is 
<u>And, remember that</u> we need to keep the value of the expression unchanged. This means that we must multiply both the numerator and the denominator by the same value
<u>Therefore:</u>
You should multiply the expression by
in order to rationalize the denominator
Hope this helps :)