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Bunuel
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What is the square root of 12345654321 ? 04 Jan 2021, 04:05
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A
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

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25% (medium)

Question Stats:

72% (01:24) correct 28% (01:39) wrong based on 260 sessions

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What is the value of \(\sqrt{12,345,654,321}\) ?

A. 111,111
B. 112,311
C. 121,212
D. 123,211
E. 132,121


Don't use a calculator ;) ;) ;)

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What is the square root of 12345654321 ?

A) 121212
B) 123211
C) 111111
D) 132121
E) 112311
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A
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What is the square root of 12345654321 ? 04 Jan 2021, 04:09
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11*11 = 121
111*111= 12321
11111*11111= 1234321
.
.
111111*111111=12345654321

Hence, A
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What is the square root of 12345654321 ? 04 Jan 2021, 04:16
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By discarding options:

C) Not the answer, you will have 4 as units digit
E) Not the answer, you will have 4 as tens digit

B/D, same reasoning, for example for B you have:

112,311x
112,311
----------
112311
112311
-----------
1235421 (you have more than 3 at the hundreds, out)

Answer is A).
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What is the square root of 12345654321 ? 04 Jan 2021, 04:17
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The answer is A

11*11 = 121
111*111= 12321
11111*11111= 1234321
.
.
111111*111111=12345654321

From the above explanation, you can notice a pattern: the middle number is equal to the length of the number, i.e., the number of ones, and then the natural count of numbers are mirrored from the middle number through 1. This is due to the stacking of numbers like so in long multiplication.

By looking at the individual digits of the number in question, it seems to be a natural sequence from 1 through 6 then back to 1. The middle number is 6, hence the answer is A
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What is the square root of 12345654321 ? 04 Jan 2021, 08:24
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Bunuel
What is the value of \(\sqrt{12,345,654,321}\) ?

A. 111,111
B. 112,311
C. 121,212
D. 123,211
E. 132,121
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12,345,654,321 , separate the number in order .....

12,345,654,321 --------> 12345|6|54321

Now, check the units digit....

So, Units digit of \(\sqrt{12,345,654,321}\) must be 1 , only options (A) , (D) & (E) are left....

Now, since the numbers are in order from left to right and from right to left, the square root must be in the same order...

Hence, Among the given options, only (A) fits in perfectly as our Answer!!
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What is the square root of 12345654321 ? 20 Jun 2025, 02:30
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