A) 11
B) 21
C) 22
D) 23
E) 32
Can someone assist with this one? Thank you
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Solve for n. Exponent question
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guerrero
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4^11 can be written as (2^2)^11 = 2^22
10^n can be written as (5x2)^n = 5^n x 2^n
so , 5^21 x 2^22 = 2x 2^n x 5^n
= 2^n+1 x 5^n
now you can safely say that n=21
OA [spoiler]21
Hope its clear[/spoiler]
10^n can be written as (5x2)^n = 5^n x 2^n
so , 5^21 x 2^22 = 2x 2^n x 5^n
= 2^n+1 x 5^n
now you can safely say that n=21
OA [spoiler]21
Hope its clear[/spoiler]
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Anju@Gurome
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(5^21)*(4^11) = (5^21)*(2^22) = 2*(5^21)*(2^21) = 2*[(2*5)^21] = 2*(10^21)krubinoff wrote:If 5^21 x 4^11 = 2 x 10^n what is the value of n?
So, n must be equal to 21.
The correct answer is B.
Anju Agarwal
Quant Expert, Gurome
Backup Methods : General guide on plugging, estimation etc.
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Quant Expert, Gurome
Backup Methods : General guide on plugging, estimation etc.
Wavy Curve Method : Solving complex inequalities in a matter of seconds.
§ GMAT with Gurome § Admissions with Gurome § Career Advising with Gurome §
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Anju@Gurome
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The easiest solution for this problem is to identify that only source of 5 in the right-hand side of the equation is 10^n. So, number of 5s in the right-hand side is n.
And, number of 5s in the left-hand side is 21.
So, n = 21
The correct answer is B.
And, number of 5s in the left-hand side is 21.
So, n = 21
The correct answer is B.
Anju Agarwal
Quant Expert, Gurome
Backup Methods : General guide on plugging, estimation etc.
Wavy Curve Method : Solving complex inequalities in a matter of seconds.
§ GMAT with Gurome § Admissions with Gurome § Career Advising with Gurome §
Quant Expert, Gurome
Backup Methods : General guide on plugging, estimation etc.
Wavy Curve Method : Solving complex inequalities in a matter of seconds.
§ GMAT with Gurome § Admissions with Gurome § Career Advising with Gurome §
