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X is rounded

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X is rounded

by Xbond » Fri Aug 14, 2009 12:28 am
Hi there,

I would like to know the simplest process to resolve this DS. Explanation is requested.

What is the result when x is rounded to the nearest hundredth ?

(1) When x is rounded to the nearest thousandth the result is 0.455
(2) The thousandths digit of x is 5
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by Bryant@VeritasPrep » Fri Aug 14, 2009 6:05 am
I guess the answer would be .46 since the thousandth digit being 5 would round up the hundredths digit to 6. The answer would be insufficient, however if all we knew was (1) since the number .4546 would be rounded to .455 but not .456 make sense?
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Re: X is rounded

by shahdevine » Fri Aug 14, 2009 6:36 am
Xbond wrote:Hi there,

I would like to know the simplest process to resolve this DS. Explanation is requested.

What is the result when x is rounded to the nearest hundredth ?

(1) When x is rounded to the nearest thousandth the result is 0.455
(2) The thousandths digit of x is 5
answer b.

to find x rounded to nearest hundredth, we are dependent on thousandths digit.

1) x rounded to nearest thousandths digit means thousandths could have been 5 or 4 depending on ten thousandths digit which we don't know. If that's the case x, rounded to nearest hundredths is uncertain. Insufficient

2) we know the thousands digit so x rounded to nearest hundredths would have 6 in hundredths. Sufficient.
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by robbie523 » Fri Aug 14, 2009 9:53 am
the answer should be C!!!!!

since when you round to the nearst thousandth there are two possibilit for the the thousandth is either a 4 rounded to 5, or it was a 5 all alone.
so, statement one, insufficient


Stm 2, only give you the thousandth digit, but without give you the other digits in front of it. the value can not be derived out.


so 1)+2) can 100% assure the value to be 0.46
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by sbasha » Fri Aug 14, 2009 10:47 am
The answer has to be "C"

Stmt 1 says x = 0.455 , you could possible arrive here by two ways
may be from 0.4545 or from 0.4554. so ans: b,c,e.

Stmt 2 says "The thousandths digit of x is 5" = we can assume anything possible. ans : c or e

Combining 1 and 2 :

give us the number in red : which we want


Hope its fine.
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by imhimanshu » Sun Aug 16, 2009 5:52 am
found it somewhere......

When rounding a number to the nearest hundredth, the result depends ONLY on the value of thousandth digit of the number.
If the thousandth digit is LESS than 5 then you keep the hundredth digit as is.
If the thousandth digit is EQUAL to or GREATER than 5, then you add one to the value of the hundredth digit.
The value of digits to the left of the hundredth digit remains the same.

The same rule applies to rounding to any unit, it only depends on the value of the digit immediately to the right of the digit you are rounding up to, and does not affect the value of any of the digits to the left of the one that you are rounding up to.

Also note that there is a difference between the hundreds digit and the hundredth digit; the first refers to the digit which is 3 units to the left of the decimal place and the latter refers to the digit which is 2 units to the right of the decimal place.

Question stem:
x rounded to the nearest hundredth = ?

First statement:
x rounded to the nearest thousandth = 0.455
This is not sufficient since we don't know if before the rounding the thousandth digit was 4 (which will result in x=0.45) or 5 (which will result in x=0.46).

Second statement:
The statement only gives information on the value of thousandth digit of x, but does not give any information on any of the other digits of x.
Not sufficient.

Both statements:
x=0.46 when rounded to the nearest hundredth.
Sufficient.

Answer is C
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by mehravikas » Sun Aug 16, 2009 9:04 pm
Sorry but why not A

Number is 0.455Y so number could be

0.4547 or 0.4553

Now when X is rounded to nearest hundredth decimal would lead to the same value because thousandth digit of the decimal is not greater than 5
robbie523 wrote:the answer should be C!!!!!

since when you round to the nearst thousandth there are two possibilit for the the thousandth is either a 4 rounded to 5, or it was a 5 all alone.
so, statement one, insufficient


Stm 2, only give you the thousandth digit, but without give you the other digits in front of it. the value can not be derived out.


so 1)+2) can 100% assure the value to be 0.46
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by robbie523 » Sun Aug 16, 2009 9:21 pm
Number is 0.455Y so number could be

0.4547 or 0.4553

Now when X is rounded to nearest hundredth decimal would lead to the same value because thousandth digit of the decimal is not greater than 5

what if is 0.4547, or 0.4541? but if the thousandths is 5, then doesn't matter no more, 0.4551 or 0.4559, would be the same for the hundredths
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Re: X is rounded

by pardeepnbp » Sun Aug 16, 2009 9:49 pm
[quote="Xbond"]Hi there,

I would like to know the simplest process to resolve this DS. Explanation is requested.

What is the result when x is rounded to the nearest hundredth ?

(1) When x is rounded to the nearest thousandth the result is 0.455
(2) The thousandths digit of x is 5[/quote]

Statement 1 is insufficient because it is telling the thousandth digit can be 5 or less than 5 which lead us to infer the the result of x is either .45 or .46. For example the actual figure before rounding to thousandth may be .4549 or .4553 or
Statement 2 is telling us the value of thousandth place but insufficient alone as will not infer the result of X

BY combining 2 statements we can infer the result that X will be .46 because the 5 at the thousandth will change the digit at the hundredth place
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by Xbond » Mon Aug 17, 2009 1:04 am
many thks guys

OA is C
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