If k is a positive integer and n = 1.7 x 10^k, what is the value of n?
1. n^2 = 2.89 x 10^10
2. 20,000 < n < 200,000
OA: D
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Exponents question- difficult
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kmittal82
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(1)
n = +- [ sqrt(2.89) x 10^5]
Ofcos, since k is positive, the negative root is eliminated, hence we are left with only 1 value for n
SUFFICIENT
(2)
Since k is an integer, only 1 value of k will satisfy the given inequality and will put n at 170,000.
SUFFICIENT
Hence (D)
n = +- [ sqrt(2.89) x 10^5]
Ofcos, since k is positive, the negative root is eliminated, hence we are left with only 1 value for n
SUFFICIENT
(2)
Since k is an integer, only 1 value of k will satisfy the given inequality and will put n at 170,000.
SUFFICIENT
Hence (D)
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pemdas
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clearly it's dHG10 wrote:If k is a positive integer and n = 1.7 x 10^k, what is the value of n?
1. n^2 = 2.89 x 10^10
2. 20,000 < n < 200,000
OA: D
st(1) implies n^2=(1.7*10^5)^2 not usual |n|=|1.7*10^5| but straight n=1.7*10^5 because the right side of n always stays positive. Hence n=170,000
st(2) again one possibility exists for k=5 and 20,000 < n=170,000 < 200,000
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killer1387
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1.HG10 wrote:If k is a positive integer and n = 1.7 x 10^k, what is the value of n?
1. n^2 = 2.89 x 10^10
2. 20,000 < n < 200,000
OA: D
n^2= 1.7^2*10^10
sufficient i.e. n will be in +- form but n is positive
2.
for k =5 unique value
sufficient
hence D
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Troika
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Thanks!killer1387 wrote:1.HG10 wrote:If k is a positive integer and n = 1.7 x 10^k, what is the value of n?
1. n^2 = 2.89 x 10^10
2. 20,000 < n < 200,000
OA: D
n^2= 1.7^2*10^10
sufficient i.e. n will be in +- form but n is positive
2.
for k =5 unique value
sufficient
hence D
