Aptitude - Square Root and Cube Root - Discussion

Discussion Forum : Square Root and Cube Root - General Questions (Q.No. 3)
3.
The least perfect square, which is divisible by each of 21, 36 and 66 is:
213444
214344
214434
231444
Answer: Option
Explanation:

L.C.M. of 21, 36, 66 = 2772.

Now, 2772 = 2 x 2 x 3 x 3 x 7 x 11

To make it a perfect square, it must be multiplied by 7 x 11.

So, required number = 22 x 32 x 72 x 112 = 213444

Discussion:
80 comments Page 3 of 8.

Malakarsidda said:   1 decade ago
How to sole this step 2772 = 2 x 2 x 3 x 3 x 7 x 11?

Prashant said:   1 decade ago
For LCM 21, 36 & 66:

3/21 36 66.

2/7 12 22.

3/7. 6. 11.

2/7. 2. 11.

7. 1. 11.

3 x 3 x 2 x 2 x 7 x 11 = 213444.

Tejaswini said:   1 decade ago
How it is possible?

Raju said:   1 decade ago
2x2x3x3x7x11 = 2772.

Here all are pair numbers but 7 & 11 are single numbers that's why we multiple by 7 & 11 again.

Santosh said:   1 decade ago
Take that example.

Take LCM of that numbers.

LCM (21, 36, 66) = 2*3*7*2*6*11==> 2*3*7*2*3*11==> 2^2*3^2*11*7.

To make above as perfect square we multiply with 11 and 7.

So (2^2*3^2*7*11)*7*11 = 213444.

Ravinesh kumar said:   10 years ago
I am not satisfy with this solution.

Ravinesh kumar said:   10 years ago
This solution is not satisfactory.

Yassmin said:   9 years ago
A square number is when you times a number or numbers to itself.

Harish said:   9 years ago
Is there any other method to solve the question? If yes please tell me the trick.

Ganesh Policherla said:   9 years ago
We can get the perfect square must multiplied 7 x 11.


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