Aptitude - Decimal Fraction - Discussion

Discussion Forum : Decimal Fraction - General Questions (Q.No. 8)
8.
The expression (11.98 x 11.98 + 11.98 x x + 0.02 x 0.02) will be a perfect square for x equal to:
0.02
0.2
0.04
0.4
Answer: Option
Explanation:

Given expression = (11.98)2 + (0.02)2 + 11.98 x x.

For the given expression to be a perfect square, we must have

11.98 x x = 2 x 11.98 x 0.02 or x   = 0.04

Discussion:
27 comments Page 2 of 3.

Swathi said:   8 years ago
Thanks @Tushar.

Vaishu said:   8 years ago
Thanks @Nandraj.

Pinku kumar singh said:   8 years ago
Thanks for the explanation.

Ssundaram said:   8 years ago
Thanks for the detailed explanation @Tushar, @Ram, @Nandaraj.

Bipul Raj Dahal said:   7 years ago
Thanks @Nandaraj.

JSubba said:   7 years ago
Simple explanation.

For it to be a perfect square it should be like this: a^2 + 2ab + b^2 So what's missing in that equation to be a perfect square is 2b so here b is 0.02 so 2*0.02 = 0.04.
(6)

Kajal said:   7 years ago
Here, it is given as 11.98 xx.
Then why did u take 2ab=11.98x? Please explain it.

Parthipan said:   6 years ago
Thanks @Nandaraj.

Abhilash said:   5 years ago
Compare with [ (a+b) ^2 ] formula.
(3)

Shweta said:   5 years ago
I think the ans should be 0.2.

(11.98)^2+2*11.98*0.02 +(0.02)^2.

2*0.02= 0.04=x^2.
x=0.2.
(3)


Post your comments here:

Your comments will be displayed after verification.