Rounded to the nearest hundredth - clarify meaning

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I know this is easy, but I'm confused, so please let me know what is the official meaning for this:

A number is rounded to the nearest 'hundredth'
Does it mean: the right side digit (thousandth) is being taken out?
1.235 = 1.24 ?

Or Does it mean: the digit being rounded is being taken out?
1.235 = 1.2 ?

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by Night reader » Mon Nov 29, 2010 10:32 pm
clawhammer wrote:I know this is easy, but I'm confused, so please let me know what is the official meaning for this:

A number is rounded to the nearest 'hundredth'
Does it mean: the right side digit (thousandth) is being taken out?
1.235 = 1.24 ?

Or Does it mean: the digit being rounded is being taken out?
1.235 = 1.2 ?
I believe it's the first option: the right side digit (thousandth) is being taken out
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by Geva@EconomistGMAT » Tue Nov 30, 2010 12:02 am
Night reader wrote:
clawhammer wrote:I know this is easy, but I'm confused, so please let me know what is the official meaning for this:

A number is rounded to the nearest 'hundredth'
Does it mean: the right side digit (thousandth) is being taken out?
1.235 = 1.24 ?

Or Does it mean: the digit being rounded is being taken out?
1.235 = 1.2 ?
I believe it's the first option: the right side digit (thousandth) is being taken out
Correct. when rounding to the nearest hundredth, go to the hundredth digit and look at the next digit:
if the next digit is 0-4, round down: lop of everything to the right of the hundredths digit, but leave the hundredth digit as is.
1.234 rounded to 1.23

If the next digit is 5-9, round up: lop off everything to the right of the hundredths digit, add 1 to the hudnredth digit itself:
1.251 rounded to 1.26
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by clawhammer » Tue Nov 30, 2010 3:59 am
Dear All,

Thanks for your input. Please explain me what the MGMAT question (attached) asks?

Image

If the number is rounded to the nearest hundredth, why would the tenths digit even change? shouldn't it remain 1?

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by Geva@EconomistGMAT » Tue Nov 30, 2010 4:05 am
clawhammer wrote:Dear All,

Thanks for your input. Please explain me what the MGMAT question (attached) asks?

Image

If the number is rounded to the nearest hundredth, why would the tenths digit even change? shouldn't it remain 1?
I agree with you - the tenth digit should not change when rounding to the hundredth. Perhaps one of the MGMAT experts can comment? What are we missing?
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by rishab1988 » Tue Nov 30, 2010 5:39 am
The answer is B.The disagree that this problem has ambiguity,which can be possible,as I have seen, in some MGMAT questions.

This question requires you to use your wits but it is certainly doable!

I got this question in MGMAT CAT and got it right.[got Q51]

The number = 3.1n5

Let number be = 3.145

Round it to nearest hundred.What do you get? 3.15

If the number is 3.155? 3.16

But if the number is 3.195? 3.20

Reason:

Because 5 is in thousandths place the hundredths digit will always be rounded up.But if the hundredths digit becomes a 2 digit no? 10.Then the tenth's digit too would have to be rounded up. to give 3.20

For eg:

I say you got 3.95 GPA in undergrad.The B-school asks you to round your under grad GPA to the nearest tenth.What would you say?

You would say 4! :)

If I you have a 3.94 GPA?

You would say 3.9 :(

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by gdk800 » Tue Nov 30, 2010 6:33 am
Geva wrote:

Correct. when rounding to the nearest hundredth, go to the hundredth digit and look at the next digit:
if the next digit is 0-4, round down: lop of everything to the right of the hundredths digit, but leave the hundredth digit as is.
1.234 rounded to 1.23

If the next digit is 5-9, round up: lop off everything to the right of the hundredths digit, add 1 to the hudnredth digit itself:
1.251 rounded to 1.26


Geva,

I think there is a problem with your second example.

If the next digit is 5-9, round up: lop off everything to the right of the hundredths digit, add 1 to the hundredth digit itself:
1.251 rounded to 1.26


If we round off 1.251 to the nearest hundredth, we would obtain 1.25 and not 1.26 since 1 in the thousandth place is less than 5.

But in case we take the number to be 1.257 than the rounding off to nearest hundredth should give us 1.26.

Please correct me if i am wrong.

Thanks :)

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by rishab1988 » Tue Nov 30, 2010 6:45 am
Please specify "highlight" with what you are having trouble with.I am not able to understand what you are trying to say..

What you are saying is exactly what I said..

If I you have a 3.94 GPA? What is your GPA rounded to nearest tenth?

You would say 3.9.

I will give you questions.Provide answers to those questions.This way I might understand what you are having trouble with.

1) Round 1.251 to the nearest hundredth
2) Round 1.255 to the nearest hundredth
3) Round 1.291 to the nearest hundredth
4) Round 1.295 to the nearest hundredth.

We round up the second last digit if the last digit is 5 or more.We drop the last digit and keep the second last digit when the last digit is 4 or less.
Last edited by rishab1988 on Tue Nov 30, 2010 6:51 am, edited 1 time in total.

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by gdk800 » Tue Nov 30, 2010 6:50 am
Rishab,

The reply doesn't concerns your answer because i agree with your solution and its the same answer and reasoning i had in my mind.

The post is meant to clarify a doubt cleared by Geva in his first post in this thread.

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by rishab1988 » Tue Nov 30, 2010 6:54 am
Geva@MasterGMAT wrote:
Night reader wrote:
clawhammer wrote:I know this is easy, but I'm confused, so please let me know what is the official meaning for this:

A number is rounded to the nearest 'hundredth'
Does it mean: the right side digit (thousandth) is being taken out?
1.235 = 1.24 ?

Or Does it mean: the digit being rounded is being taken out?
1.235 = 1.2 ?
I believe it's the first option: the right side digit (thousandth) is being taken out
Correct. when rounding to the nearest hundredth, go to the hundredth digit and look at the next digit:
if the next digit is 0-4, round down: lop of everything to the right of the hundredths digit, but leave the hundredth digit as is.
1.234 rounded to 1.23

If the next digit is 5-9, round up: lop off everything to the right of the hundredths digit, add 1 to the hudnredth digit itself:
1.251 rounded to 1.26
I think Geva made a typo.1.251 will round to 1.25 and not 1.26.You are right.