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SRK
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Rounding off rules

by SRK Tue May 01, 2012 8:50 pm

Can some one please tell me the rules to rounding off the digits? I am having confusion on how to round of to nearest digits.

say 1.485 -> rounded to nearest hundredths and nearest tenths
rajagopalan.srikanth
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Re: Rounding off rules

by rajagopalan.srikanth Wed May 02, 2012 9:37 pm

can some one help with the rounding of rules?
jnelson0612
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Re: Rounding off rules

by jnelson0612 Sun May 20, 2012 4:46 pm

SRK Wrote:Can some one please tell me the rules to rounding off the digits? I am having confusion on how to round of to nearest digits.

say 1.485 -> rounded to nearest hundredths and nearest tenths


Sure! Let's think about rounding. If I am rounding to a particular place, I only must consider the place to the right of the place we are interested in. For example, if I have 650 and am rounding to the nearest hundred, I consider the tens place. It has a 5, and I round up with a 5. So I round 650 to 700.

If I am rounding 43 to the tens place, I consider the ones place. It has a 3, so I round down. 43 rounds to 40.

Now, let's look at this one. "tenths" is the place to the right of the point (the 4 is there); "hundredths" is two places to the right (the 8 is there). The 5 is in the thousandths place.

Let's round 1.485 to the tenths place. We only need to consider the number in the hundredths place, 8. Round up. 1.485 rounds to 1.5.

Now let's round 1.485 to the hundredths place. We must consider the number in the thousandths place, 5. Round up. 1.485 rounds to 1.49.

Please let me know if I can offer further clarification.
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rohan.nanda
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Re: Rounding off rules

by rohan.nanda Thu Jul 05, 2012 10:59 pm

Hi,

How do you round-off the following and the likes of it:

-round off 290 miles to the nearest 10 miles
-round off 12 gallons to the nearest gallon
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Re: Rounding off rules

by tim Fri Jul 06, 2012 9:06 am

they are already rounded off..
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Re: Rounding off rules

by amycompton Fri Jul 27, 2012 7:24 am

Here's the general rule for rounding:

If the number you are rounding is followed by 5, 6, 7, 8, or 9, round the number up. Example: 38 rounded to the nearest ten is 401

If the number you are rounding is followed by 0, 1, 2, 3, or 4, round the number down. Example: 33 rounded to the nearest ten is 30

Rounding fractions works exactly the same way as rounding whole numbers. The only difference is that instead of rounding to tens, hundreds, thousands, and so on, you round to tenths, hundredths, thousandths, and so on.

7.8199 rounded to the nearest tenth is 7.8
1.0621 rounded to the nearest hundredth is 1.06
3.8792 rounded to the nearest thousandth is 3.879
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Re: Rounding off rules

by tim Fri Jul 27, 2012 8:02 am

.
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rkafc81
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Re: Rounding off rules

by rkafc81 Sun Oct 14, 2012 9:25 am

hi

what's the rule for rounding times? I saw a question recently where it said "labour for car repairs was $45 and hour, rounded to the nearest 1/2 hour". The question said all the car repairs took 3.5 hours. what if it took 3.75 hours, would I round to 4 hours, or to 3 1/2 hours?

thanks
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Re: Rounding off rules

by jnelson0612 Mon Oct 15, 2012 10:31 pm

n2739178 Wrote:hi

what's the rule for rounding times? I saw a question recently where it said "labour for car repairs was $45 and hour, rounded to the nearest 1/2 hour". The question said all the car repairs took 3.5 hours. what if it took 3.75 hours, would I round to 4 hours, or to 3 1/2 hours?

thanks


We would round 3.75 to 4 hours, since it is exactly halfway between 3.5 and 4 hours and we always round up when we are halfway between.
Jamie Nelson
ManhattanGMAT Instructor