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#1 2015-10-06 16:52:46

pari_alf
Member
Registered: 2013-12-01
Posts: 85

this value -1.1576e-005 is small or big? [edited]

Hi guys,

Please help me to understand that how to identify this value is too big or too small.
I always misunderstand it .

-1.1576e-005

4e-008

thanks

Last edited by pari_alf (2015-10-06 18:02:46)

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#2 2015-10-06 17:51:37

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: this value -1.1576e-005 is small or big? [edited]

Hi;

That is scientific notation:

-1.1576e-005 = -.000011576

4e-008 = .00000004


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#3 2015-10-06 18:00:16

pari_alf
Member
Registered: 2013-12-01
Posts: 85

Re: this value -1.1576e-005 is small or big? [edited]

I want to understand how to say that this value is too large or too small.


bobbym wrote:

Hi;

That is scientific notation:

-1.1576e-005 = -.000011576

4e-008 = .00000004

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#4 2015-10-06 18:50:03

Bob
Administrator
Registered: 2010-06-20
Posts: 10,143

Re: this value -1.1576e-005 is small or big? [edited]


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#5 2015-10-06 19:02:56

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: this value -1.1576e-005 is small or big? [edited]

I want to understand how to say that this value is too large or too small.

You edited the question after I answered it.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#6 2015-10-06 19:19:28

pari_alf
Member
Registered: 2013-12-01
Posts: 85

Re: this value -1.1576e-005 is small or big? [edited]

yes i edited because i understood after your reply that what i need to understand,. sorry to do it.

bobbym wrote:

I want to understand how to say that this value is too large or too small.

You edited the question after I answered it.

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#7 2015-10-06 19:29:08

pari_alf
Member
Registered: 2013-12-01
Posts: 85

Re: this value -1.1576e-005 is small or big? [edited]

Hi Bob,

Thanks for directing me to scientific notation explanation.

if i understand correctly than

-1.1576e-005 = -1.1576 x 10^005 [i think 005 mean -5]
so it will be -1.1576 x 10^-5 => 0.00011576  (i think it is a big value)

and

4e-008 = 4 x 10^008  [i think 008 mean -8]
so it will be -4 x 10^-8 => -0.000000004 (i think it is small value)

Am i right?

bob bundy wrote:

Last edited by pari_alf (2015-10-06 19:37:02)

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#8 2015-10-06 20:10:36

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: this value -1.1576e-005 is small or big? [edited]

Hi;

4 x 10^(-8) means 4 x 1/10^8 or for convenience move the decimal point 8 places to the left, The answer is .00000004. There is no sign change.

Whether to say that is a small number or not depends on how you define the words large and small.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#9 2015-10-07 19:35:45

Bob
Administrator
Registered: 2010-06-20
Posts: 10,143

Re: this value -1.1576e-005 is small or big? [edited]

hi pari_alf


-1.1576e-005 = -1.1576 x 10^005 [i think 005 mean -5] correct

so it will be -1.1576 x 10^-5 => 0.00011576  (i think it is a big value)

Two things wrong here.  The first minus means the number is negative.  And the decimal point is misplaced.

The way I get the decimal point right is by moving it 5 places left.

and

4e-008 = 4 x 10^008  [i think 008 mean -8]correct

so it will be -4 x 10^-8 => -0.000000004 (i think it is small value)

again two errors I afraid.  sad 

A leading minus makes the number negative.  This time there is no leading minus so the number is positive.

The -8 on the power of ten means move the point 8 places left.

If you go back to that link again you will find a 'Try It Yourself' section a little way down the page.  You can test whether you have done the conversion correctly by entering numbers in the boxes.

I agree with bobbym about whether a number is large or small.  If bacteria could talk they would say that the thickness of a human hair is large.  If you wanted to say which of the two numbers you gave was smaller then you still need to think a little as one number is negative.  If, by smaller, you mean further to the left on the number line, then -0.000011576 is smaller.  But, if you ignore negative signs and just consider which has the smaller absolute value then 0.00000004 is smaller.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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