The five steps shown will result in an expression equivalent to which

Question

Step 1: Multiply x by 3.
Step 2: Take the square root of the result of step 1.
Step 3: Take the reciprocal of the result of step 2.
Step 4: Add 1 to the result of step 3.
Step 5: Square the result of step 4.
The five steps shown will result in an expression equivalent to which of the following?

A.  \frac{1 + 3x}{3x}

B.  \frac{1 + 9x}{9x}

C.  \frac{1}{3x + 3\sqrt{3x} +1}

D.  \frac{1 + 2\sqrt{3x} +3x}{3x}

E.  \frac{1 + 6\sqrt{x} +9x}{9x}

MartyMurray · Accepted Answer

The five steps shown will result in an expression equivalent to which of the following?

Step 1: Multiply x by 3.

3x

Step 2: Take the square root of the result of step 1.

\sqrt{3x}

Step 3: Take the reciprocal of the result of step 2.

\frac{1}{\sqrt{3x}

Step 4: Add 1 to the result of step 3.

\frac{1}{\sqrt{3x}} + 1 = \frac{1 + \sqrt{3x}}{\sqrt{3x}}

Step 5: Square the result of step 4.

\frac{1 + 2\sqrt{3x} +3x}{3x}

The correct answer is (D).

gmatophobia · Answer

Very different than the traditional questions

Step 1: Multiply x by 3. Result : 3*x Step 2: Take the square root of the result of step 1. Result : \sqrt{3*x} Step 3: Take the reciprocal of the result of step 2. Result : \frac{1}{\sqrt{3*x}} Step 4: Add 1 to the result of step 3. Result : \frac{1}{\sqrt{3*x}}+1 Step 5: Square the result of step 4. Result : (\frac{1}{\sqrt{3*x}}+1)^2 (\frac{1}{\sqrt{3*x}})^2 + 1^2 + 2*(\frac{1}{\sqrt{3*x}}) \frac{1}{3x} + 1 + \frac{2}{\sqrt{3x}} Take 3x as LCM \frac{1 + 3x + 2\sqrt{3x}}{3x} Option D

Paras96 · Answer

Step 1: Multiply x by 3.
= 3x
Step 2: Take the square root of the result of step 1.
= (3x)^0.5
Step 3: Take the reciprocal of the result of step 2.
=(3x)^(-0.5)
Step 4: Add 1 to the result of step 3.
= 1 +   = ( 1 +   )/  
Step 5: Square the result of step 4.
( 1 +   )/  ^2
= ( 1 +   )^2/3x
 =  /3x

Hence D

JeffTargetTestPrep · Answer

Step 1: 3x

Step 2: √(3x)

Step 3: 1/√(3x)

Step 4: 1/√(3x) + 1 =1/√(3x) + √(3x)/√(3x) =
 /√(3x)

Step 5:  /√(3x)]^2 = 
(1 + 2√(3x) + 3x)/(3x)

Answer: D

HarshavardhanR · Answer

https://gmatclub.com/forum/download/file.php?id=83580 Harsha GMAT-Club-Forum-v206nk4f.png

reighlyschultz · Answer

What might be easier for some people in this case is to plug in a number as well since we are multiplying by 3 and then taking a square root it makes sense to take 3 as our "x".

1. 3*3=9
2. Square Root of 9 is 3
3. Reciprocal of 3 is 1/3
4.Add 1 which is 3/3 so your new number is 4/3
5. Square 4/3 to get 16/9. Which is the number you will be checking for.

A. (1+3*3)/3*3 No
B. (1+9*3)/9*3 No
ETC 
Until D where (1+2*Squared root (3*3) + 3*3)/3*3 gives us

(1+3+9)/3*3=16/9 Answer Choice D

ravjaz · Answer

Why did we not rationalise the donminator after step 4? I got confused doing this and could not get to the right answer

bumpbot · Answer

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The five steps shown will result in an expression equivalent to which

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