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For all x, the expression x* is defined to be ax + a, where a is......
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D
E
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For all \(x\), the expression \(x^*\) is defined to be \(ax + a\), where \(a\) is a constant. What is the value of \(2^*\)?
(1) \(3^* = 2\)
(2) \(5^* = 3\)
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Re: For all x, the expression x* is defined to be ax + a, where a is......
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nalinnair wrote:
For all \(x\), the expression \(x^*\) is defined to be \(ax + a\), where \(a\) is a constant. What is the value of \(2^*\)?
x* = ax + a = a (x + 1)
2* = ?
Statement 1: 3* = 2
or 3a + a = 2
a = 1/2
Hence 2* = (1/2)*(2 + 1) = 3/2
SUFFICIENT
Statement 2: 5* = 3
Or 5a + a = 3
a = 1/2
Hence 2* = (1/2)*(2 + 1) = 3/2
SUFFICIENT
Correct Option: D
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Re: For all x, the expression x* is defined to be ax + a, where a is......
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Trying to solve these equations is unnecessary and in 90% of DS questions a waste of time
A) 3a + a = 2
Linear eqn with 1 variable, 1 solution. sufficient
2) 5 a + a = 6
Same reasoning as above
Answer : D
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Joined: 27 Apr 2015
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For all x, the expression x* is defined to be ax + a, where a is......
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nalinnair wrote:
For all \(x\), the expression \(x^*\) is defined to be \(ax + a\), where \(a\) is a constant. What is the value of \(2^*\)?
Given
=>x*=ax+a
=>x*=a(x+1)
Therefore
=>2*=a(2+1)
=>2*=3a ----
(1) so if we can find the value of 'a ' we can hav the value of 2*
Now
Statement 1 says 3*=2
3*=4a from
(1) => 4a=2
=> a=2/4=1/2
sufficient
Statement 2 says 5*=3
5*=6a from
(1) => 6a=3
=> a=3/6=1/2
sufficient
Therefore option 'D'
Thanks
Originally posted by
dineshril on 19 Dec 2017, 06:47.
Last edited by
dineshril on 19 Dec 2017, 10:31, edited 1 time in total.
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Location: India
Re: For all x, the expression x* is defined to be ax + a, where a is......
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dineshril wrote:
nalinnair wrote:
For all \(x\), the expression \(x^*\) is defined to be \(ax + a\), where \(a\) is a constant. What is the value of \(2^*\)?
Given
=>x*=ax+a
=>x*=a(x+1)
Therefore
=>2*=a(2+1)
=>2*=3a ----
(1) so if we can find the value of 'a ' we can hav the value of 2*
Now
Statement 1 says 3*=2
3*=4a from
(1) => 4a=2
=> a=2/4=1/2
sufficient
Statement 2 says 5*=3
5*=6a from
(1) => 6a=3
=> a=3/6=1/2
sufficient
Therefore option 'E'
Thanks
Hi
Correct solution. But when each statement alone is sufficient to answer a question, the answer is D
I guess that was a typo
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Joined: 27 Apr 2015
Posts: 41
Re: For all x, the expression x* is defined to be ax + a, where a is......
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amanvermagmat wrote:
dineshril wrote:
nalinnair wrote:
For all \(x\), the expression \(x^*\) is defined to be \(ax + a\), where \(a\) is a constant. What is the value of \(2^*\)?
Given
=>x*=ax+a
=>x*=a(x+1)
Therefore
=>2*=a(2+1)
=>2*=3a ----
(1) so if we can find the value of 'a ' we can hav the value of 2*
Now
Statement 1 says 3*=2
3*=4a from
(1) => 4a=2
=> a=2/4=1/2
sufficient
Statement 2 says 5*=3
5*=6a from
(1) => 6a=3
=> a=3/6=1/2
sufficient
Therefore option 'E'
Thanks
Hi
Correct solution. But when each statement alone is sufficient to answer a question, the answer is D
I guess that was a typo
Hi Aman
Thanks for the correction. Its 'D'
Re: For all x, the expression x* is defined to be ax + a, where a is...... &nbs
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19 Dec 2017, 10:30
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92% (01:02) correct 
