Aptitude - Square Root and Cube Root - Discussion
Discussion Forum : Square Root and Cube Root - General Questions (Q.No. 2)
2.
| What should come in place of both x in the equation | x | = | 162 | . |
| 128 | x |
Answer: Option
Explanation:
| Let | x | = | 162 |
| 128 | x |
Then x2 = 128 x 162
= 64 x 2 x 18 x 9
= 82 x 62 x 32
= 8 x 6 x 3
= 144.
x = 144 = 12.
Discussion:
35 comments Page 1 of 4.
S.ramkumar said:
1 decade ago
You split 162=18*9 how we can understand this because there are so many possibles are there to split 162 and how we can find this exact split.
Sreedevi said:
1 decade ago
You can see that 162 is divisible by 9.i.e.(1+6+2)=9 which is a multiple of 9.so it makes calculation easier if one factor is a perfect square. You can split 162 as 81*2 also where 81 is a perfect square.
Kumari said:
1 decade ago
@sreedevi,
Thanks for tip.
But,I think it is bit difficult to get this correctly.
Mostly we need to think in terms of squares and then look for which one will give 162
Thanks for tip.
But,I think it is bit difficult to get this correctly.
Mostly we need to think in terms of squares and then look for which one will give 162
Sumi said:
1 decade ago
Is there any short tricks to find square root and cube root ?
Proek said:
1 decade ago
-12 is the valid answer too!
Jiyan prathap said:
1 decade ago
There is a short cut to find square root
For Eg: 144 which is the square of 12.
First leave the last two digits of 144. The remaining is 1, 1 comes in 1 table alone.
Hence the first number of the answer is 1.
To find the second digit always add 1 to the first digit of the answer i.e 1+1=2 which is the second digit. Combine together the answer is 12.
For Eg: 144 which is the square of 12.
First leave the last two digits of 144. The remaining is 1, 1 comes in 1 table alone.
Hence the first number of the answer is 1.
To find the second digit always add 1 to the first digit of the answer i.e 1+1=2 which is the second digit. Combine together the answer is 12.
Kalyani said:
1 decade ago
@Jiyan prathap. Can we find square root of all others too by using this method?
Pradeep said:
1 decade ago
128*162 = 20736.
Now find the square root by long division method.
Square root = 144.
Thus x = 12.
Now find the square root by long division method.
Square root = 144.
Thus x = 12.
Ravi said:
1 decade ago
@Jiyan prathap.
By using your method find the square root of 196.
By using your method find the square root of 196.
Govind said:
1 decade ago
The above said method is easy to find. Because we can split the no by using the square values we know.
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