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:
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 6 of 8.
Sudarshana said:
1 decade ago
I found the answer correct when I tried to divide each of the options by 21, 36, 66. And only opt. A was found to divide with all three without any fraction.
Is it the write method ?
Is it the write method ?
Atul said:
1 decade ago
2/21,36,66
2/21.18,33
3/21,9,33
3/7,3,11
/7,1,11
So L.C.M : 2*2*3*3*7*11 = 2772.
2/21.18,33
3/21,9,33
3/7,3,11
/7,1,11
So L.C.M : 2*2*3*3*7*11 = 2772.
Mohit said:
1 decade ago
Hey guys its simple. Please refer rakhi's answer. !
Sams said:
1 decade ago
21, 36,66 which is divisible by 6
then we have to check hw many answer divisible by 6 and find the least one
then we have to check hw many answer divisible by 6 and find the least one
VKS said:
1 decade ago
LCM = 2772
REQ TO MULTI 2772*11*7 TO MAKE PERFECT SQR
= 2772*77=213444
REQ TO MULTI 2772*11*7 TO MAKE PERFECT SQR
= 2772*77=213444
Vijay said:
1 decade ago
How can 22*32*72*112 = 213444 this is done in less than 10 sec?
Raju kaki said:
1 decade ago
3/21,36,66
2/7,12,22
7,6,11
so l.c.m=3*2*7*6*11
=3^2*2^2*7*11
to make perfect square we have to multiply with 7 and 11the it turns
=3^2*2^2*7^2*11^2
2/7,12,22
7,6,11
so l.c.m=3*2*7*6*11
=3^2*2^2*7*11
to make perfect square we have to multiply with 7 and 11the it turns
=3^2*2^2*7^2*11^2
Kumar said:
1 decade ago
How can 22 x 32 x 72 x 112 = 213444 - this be done in less than 10 secs?
Sowjanya said:
1 decade ago
It is very difficult to divide all the options with the given numbers. It will take more time it is better to go to the LCM/HCF methods. Its very simple that multiplying 7 and 11 to make all the number a perfect square and multiply all the numbers we will get answers.
Deepu said:
1 decade ago
The lcm of 21,36,66=2772
I have a simple method.
213444is divisible by 21 comes 10164
and 36 to comes 5929
and 6 to comes 3234
So finaly it is divisible by 3 numbers.
I have a simple method.
213444is divisible by 21 comes 10164
and 36 to comes 5929
and 6 to comes 3234
So finaly it is divisible by 3 numbers.
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