rounding question - comparing a DS and a PS ques in gmat11Re

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What part of these two questions am i misunderstanding? I'm comparing DS58 with PS129

in DS58, when d a number, is rounded to the nearest tenth , the result is .5, so the book assumes it ranges between 0.45 to 0.54 and it makes sense. it also says that when d is rounded to the nearest integer, it values is 1, so the book assumes it ranges from .5 to 1.4, again i get this.

What is confusing is how it is dealth with in question PS129, details below. you can review the quetion stem in the book but the answer comes out to 284/12.5 to 295/11.4 but I thought if we rounded them based on basic math rounding rules, it should be 285/12.4 to 294/11.5. based on the logic that if a number rounded to the nearest tens is 290, it must range from 285 to 294, same thing with 12 gallons, if its rounded to the units digit, then it must be between 11.5 to 12.4, how does the book get those numbers?

Can someone help me out please!!

thanks
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by simplyjat » Sun Apr 27, 2008 9:02 pm
I personally feel that the answer choices mentioned for PS129 are wrong. Range for 290 rounding should be 285 to 294, and not 285 to 295. But when you look closely at the answer choices all make the same mistake.

So in questions like these, You can ignore the rule and just assume a misprinting: 295 instead of 294.
simplyjat

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by freedsl » Mon Apr 28, 2008 8:24 am
thanks bud, that driving me crazy!! :)