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Sub 505 (Easy)|   Algebra|      
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Bunuel
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1051^2 − 1049^2 = ? 18 May 2021, 07:45
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E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

5% (low)

Question Stats:

92% (00:33) correct 8% (01:18) wrong based on 59 sessions

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Date
Time
Result
Not Attempted Yet
\(1051^2 − 1049^2 = ?\)

A. 4
B. 16
C. 1050
D. 2100
E. 4200
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E
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1051^2 − 1049^2 = ? 18 May 2021, 07:47
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1051^2−1049^2
= (1051+1049)(1051-1049)
= (2100)(2)
= 4200

Answer E
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Anisha1637
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1051^2 − 1049^2 = ? 18 May 2021, 07:50
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Using the formula of (a^2-b^2)
(1051-1049)(1051+1049)
2*2100
4200

IMO E

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Showmeyaa
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1051^2 − 1049^2 = ? 18 May 2021, 07:52
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Bunuel
\(1051^2 − 1049^2 = ?\)

A. 4
B. 16
C. 1050
D. 2100
E. 4200
Show more

\(1051^2 − 1049^2 =\)
\((1050 + 1)^2 - (1050 - 1)^2\)
\((1050 + 1 + 1050 - 1)(1050 + 1 - 1050 + 1)\)
\((2100)(2)\)
\(4200\) - E
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ManyataM
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1051^2 − 1049^2 = ? Updated on: 18 May 2021, 08:25
Originally posted by ManyataM on 18 May 2021, 08:17.
Last edited by ManyataM on 18 May 2021, 08:25, edited 1 time in total.
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Bunuel
\(1051^2 − 1049^2 = ?\)

A. 4
B. 16
C. 1050
D. 2100
E. 4200
Show more

IMO the answer is option E

(1051)^2 - [(1051-2)^2]
Solving the equation will give us 4200.

But when I formed the equation:

(1050+1)^2 - [(1050-1)^2]
Im not getting the same Idk why. I tried it twice.

Posted from my mobile device
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Showmeyaa
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1051^2 − 1049^2 = ? 18 May 2021, 08:21
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ManyataM
Bunuel
\(1051^2 − 1049^2 = ?\)

A. 4
B. 16
C. 1050
D. 2100
E. 4200

IMO the answer is option E

(1051)^2 - [(1051-2)^2]
Solving the equation will give us 4200.

But when I formed the equation:

(1050+1)^2 - [(1051-2)^2]
Im not getting the same Idk why. I tried it twice.

Posted from my mobile device
Show more

Hi ManyataM,
The reason why you are getting a different answer is because your breakup is wrong.
If you use the below breakup, you can not apply \(a^2 - b^2 = (a+b)(a-b)\)
(1050+1)^2 - [(1051-2)^2]
Refer to the post just above yours. I hope that helps :)
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ManyataM
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1051^2 − 1049^2 = ? 18 May 2021, 08:25
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Showmeyaa
ManyataM
Bunuel
\(1051^2 − 1049^2 = ?\)

A. 4
B. 16
C. 1050
D. 2100
E. 4200

IMO the answer is option E

(1051)^2 - [(1051-2)^2]
Solving the equation will give us 4200.

But when I formed the equation:

(1050+1)^2 - [(1051-2)^2]
Im not getting the same Idk why. I tried it twice.

Posted from my mobile device

Hi ManyataM,
The reason why you are getting a different answer is because your breakup is wrong.
If you use the below breakup, you can not apply \(a^2 - b^2 = (a+b)(a-b)\)
(1050+1)^2 - [(1051-2)^2]
Refer to the post just above yours. I hope that helps :)
Show more

Hey.. Got my mistake. Thanks. I understood it. 🤟🏻
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MathRevolution
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GMAT 1: 760 Q51 V42
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1051^2 − 1049^2 = ? 19 May 2021, 01:42
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\(a^2 - b^2 = (a - b)(a + b)\)

\(1051^2 - 1049^2 = (1051 - 1049)(1051 + 1049) = 2 * 2100 = 4200\)

Answer E
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