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
dont understand this.
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- Jose Ferreira
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The statement will be insufficient if we can name different numbers that satisfy the statement, but have different values in the tenths digit.
The first statement says the hundredths digit is 5. So, the number could be:
5.25
21.75
16.35
Insufficient
Statement 2 says that rounded to the nearest tenth, x is 54.5. That means could x could be:
54.51 -- a 5 in the tenths place
54.49 -- a 4 in the tenths place
Insufficient
Put the statements together -- then we know that the hundredths digit will cause us to round UP, and that, once we do round up, our number will be 54.5. Thus, x must equal 54.45. It's the only number that satisfies both statements.
Answer is C
The first statement says the hundredths digit is 5. So, the number could be:
5.25
21.75
16.35
Insufficient
Statement 2 says that rounded to the nearest tenth, x is 54.5. That means could x could be:
54.51 -- a 5 in the tenths place
54.49 -- a 4 in the tenths place
Insufficient
Put the statements together -- then we know that the hundredths digit will cause us to round UP, and that, once we do round up, our number will be 54.5. Thus, x must equal 54.45. It's the only number that satisfies both statements.
Answer is C
Last edited by Jose Ferreira on Mon May 18, 2009 10:06 am, edited 1 time in total.
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I missed this step and marked B. What's the thought process I need to have to avoid such mistakes?
Jose Ferreira wrote:The statement will be insufficient if we can name different numbers that satisfy the statement, but have different values in the tenths digit.
The first statement says the hundredths digit is 5. So, the number could be:
5.25
21.75
16.35
Insufficient
Statement 2 says that rounded to the nearest tenth, x is 54.5. That means could x could be:
54.51 -- a 5 in the tenths place
54.49 -- a 4 in the tenths place
Insufficient
Put the statements together, then we know that the hundredths digit will cause us to round UP, and that, once we do round up, our number will be 54.5. Thus, x must equal 54.45. It's the only number that satisfies both statements.
Answer is C