What is the value of the tenths digit of number x?

(1) The hundredths digit of x is 5
(2) Number x, rounded to the nearest tenth, is 54.5

x=a.bc --> b=?

(1) x=a.b5. Clearly insufficient to determine b.

(2) x, rounded to nearest tenth is 54.5 --> x can be for example 54.54 (meaning that c<5) OR 54.46 (meaning that c>=5). Not sufficient.

(1)+(2) c=5>=5, hence x=54.45... --> b=4. Sufficient.

Answer: C.
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Thanks Guys

OA is C

I was messing up with my rounding off concepts
Now I fixed'em ryt

Need a quick clarification on this. (I guess I don't need a clarification anymore, just thought i'd add the note below)

What is Number x, rounded to the nearest tenth here?

if x = 54.550000 ~ 54.6
if x = 54.458000 ~ 54.5

I guess I figured it out as I was typing this itself.

Note: When the digit 5, 6, 7, 8, or 9 appears in the ones place, round up; when the digit 0, 1, 2, 3, or 4 appears in the ones place, round down
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Thanks for clarifying this.
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Hi Bunuel,
Sorry for the silly question but how do we know its asking tenths digit after or before decimal?

is this question asking about tenth digit or decimal point?
i think it should be tenth decimal point,
and after rounding off it comes as 54.5 hence tenth decimal 0.5 remained as it is as hundredth digit was less than or equal to 5,
e.g number was 54.55, I round it off , it becomes 54.5, if the number was 54.56, i round it off it becomes 54.6

if you dont consider first statement then there are two possibilities 54.47 will also become 54.5 and 54.52 will also become 54.5
hence we need both statements

Hope i m making sense
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Hi All,

In this prompt, we're asked for the TENTHS digit of X? This question asks for the digit that is to the IMMEDIATE RIGHT of the decimal point.

Fact 1: The hundredths digit of X is 5

This tells us NOTHING about the tenths digit - that digit could be any integer from 0 to 9, inclusive.

eg.
X = _.05
X = _.15
X = _.25
...
X = _.95
Fact 1 is INSUFFICIENT

Fact 2: Number X, rounded to the nearest tenth, is 54.5

This Fact discusses ROUNDING. If the hundredths digit is 0-4, then we 'round down'; if the hundredths digit is 5-9, then we 'round up.'

eg.
IF.....
X = 54.49, then we would 'round up' to 54.5

X = 54.53, then we would 'round down' to 54.5

Thus, the tenths digit could be 4 or 5.
Fact 2 is INSUFFICIENT

Combined, we know...
The hundredths digit of X is 5
Number X, rounded to the nearest tenth, is 54.5

Since the hundredths digit is 5, that means that we would have to round UP to get to 54.5. Thus, X could only be 54.45
Combined, SUFFICIENT

Final Answer:

GMAT assassins aren't born, they're made,
Rich
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but why is 10th digit after decimal? why not the 10th digit before decimal? how do you get to know if theyre talking about the tenths digit of before or after decimal