61.24 x (0.998) 2 403 The expression above is approximately equal to

Question

\frac{61.24*0.998^2}{\sqrt{403}} 
The expression above is approximately equal to

(A) 1
(B) 3
(C) 4
(D) 5
(E) 6

Bunuel · Accepted Answer

SOLUTION

\frac{61.24*0.998^2}{\sqrt{403}} 
The expression above is approximately equal to

(A) 1
(B) 3
(C) 4
(D) 5
(E) 6

\frac{61.24*0.998^2}{\sqrt{403}}\approx{\frac{60*1}{\sqrt{400}}}=\frac{60}{20}=3 .

Answer: B.

bharatdivvela · Answer

it is all about approximations

the numerator 61.24*.998^2=60(approximately)
the denominator sqrt(403)= 20(approximately)

hence the value of given expression is 3.

since the accurate value is not asked, it is ok to roughly approximate the values to quickly arrive at the correct answer

beatthegmat05 · Answer

Here the key is APPROXIMATION .

0.998~1 ----> 1^2 = 1
403^1/2=20.07.... ~20

So after approximation our expression becomes - (61.24*1)/20 =3.06... ~ 3

So correct answer is (B)

nutshell · Answer

Here, it would be advisable to look at the answer choices first. Since we have small integers, it will be easier if you can approx. the values to the closest integer.

0.998 ~ 1
\sqrt{403} ~ 20
Now, since we have 20 in the denominator and the answer choices are plain integers, 61.24 can be approximated to 60, thereby giving us a value of 3.

Ans is (B)

stne · Answer

Since the question is asking for an approximate value hence the question can we written as

\frac{61.24*1^2}{\sqrt{400}}

= \frac{61.24*1^2}{20}= \frac{6124}{2000}=3

Answer B

stonecold · Answer

Nice Official Question.
Here is what i did =>
Rounding up both the numerators to the nearest integer and the denominator to the nearest tenths.
We get => \frac{60*1^2}{√400} 
=> 6/2 => 3

Hence B

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61.24 x (0.998) 2 403 The expression above is approximately equal to

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61.24 x (0.998) 2 403 The expression above is approximately equal to

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