vjns wrote:
I did not understand the explanation given in
OG 13 for this question - DS 63. Does rounding mean rounding just one number?
1. if d >= 0.51 then d >= 0.5. Also if d = 0.49 then d = 0.5. Therefore 1 is insufficient.
2. if 0.50 <= d <= 1.49 then d >= 0.5. However, can we not round 0.49 to 0.50 which in turn can be rounded to 1? Therefore, is this too not insufficient?
Kindly point out my mistake.
When rounding we should only take into the account the first dropped digit.
Rounding rulesRounding is simplifying a number to a certain place value. To round the decimal drop the extra decimal places, and if the first dropped digit is 5 or greater, round up the last digit that you keep. If the first dropped digit is 4 or smaller, round down (keep the same) the last digit that you keep.Example:
5.3485 rounded to the nearest tenth = 5.3, since the dropped 4 is less than 5.
5.3485 rounded to the nearest hundredth = 5.35, since the dropped 8 is greater than 5.
5.3485 rounded to the nearest thousandth = 5.349, since the dropped 5 is equal to 5.
If d denotes a decimal, is \(d\geq{0.5}\) ?(1) When d is rounded to the nearest tenth, the result is 0.5. This statement implies that \(0.45\leq{d}<0.55\). Not sufficient.
(2) When d is rounded to the nearest integer, the result is 1. d cannot be less than 0.5 because in this case 1 won't be the nearest integer. Sufficient.
Answer: B.
All OG13 questions with solutions:
the-official-guide-quantitative-question-directory-143450.htmlOPEN DISCUSSION OF THIS QUESTION IS HERE: if-d-denotes-a-decimal-is-d-140736.html _________________