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#101 2011-07-07 05:09:49

bob bundy
Moderator
Registered: 2010-06-20
Posts: 6,528

Re: Exponents and Scientific Notation

OK

My ruler is 1 foot = 12 inches = about 30 cm.

4.5 Liters is about 1 gallon

1 Kilogram is about 2.2 lb.

5 miles is almost exactly 8 kilometers.

See http://en.wikipedia.org/wiki/Imperial_units

if you want more.

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#102 2011-07-07 05:18:18

bob bundy
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Registered: 2010-06-20
Posts: 6,528

Re: Exponents and Scientific Notation

Incorrect answers:

1-c   

I'll post this and continue with the others.  Refresh the page to see more.

14-e

That is certainly an identified error.  I'm guessing that it is not the first.  I would have got this wrong too.  Is it something to do with how you place the conversion factors top and bottom in order to identify times and divide?  I cannot help more unless I see the 'rules' of this way of doing conversions.


17-d

Same problem here.  Your conversion was correct and so you identified an error in the question as required.  It's a layout problem again.  Sorry.

19-f

This is a GOOD ANSWER.  I've got a 0.5L orange carton in my cupboard!  The person who set this needs to go shopping!


20-f

And again here.  I don't see how we are supposed to know what size can the questioner had in mind!

Don't feel bad about those 5 questions.  In 4 out of 5 your mathematics was good.

Bob

Last edited by bob bundy (2011-07-07 05:29:00)


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#103 2011-07-07 05:18:47

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: Exponents and Scientific Notation

i dont get how c  for number one was incorrect


(x^3)^5
Ax^-15
Bx^2
Cx^8
Dx^15
Ex^-2
Fx^-8


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#104 2011-07-07 05:23:36

bob bundy
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Registered: 2010-06-20
Posts: 6,528

Re: Exponents and Scientific Notation

i dont get how c  for number one was incorrect

When you raise to a power (3) and then raise that to another power (5) the 'x' is repeated 15 times not 8.  Look back to my earlier post on this.

So 3 x 5 to get 15

not 3 + 5 to get 8

Post #102 has my explanations.

Bob

Last edited by bob bundy (2011-07-07 05:24:05)


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#105 2011-07-07 05:27:56

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: Exponents and Scientific Notation

yup i just saw that sorry 14-e and 17 19 20 are all incorrect


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#106 2011-07-07 05:30:44

bob bundy
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Registered: 2010-06-20
Posts: 6,528

Re: Exponents and Scientific Notation

I've edited # 102 to show my view on all of those.

I think you are a victim of poor questions.  Let's hope the next set are more reasonable.

With the extra knowledge that the answers we worked out yesterday were not right, I've had a look back at the conversion tables and tried to work out what was expected.

The picture below is my revised attempt at these.  I've corrected all errors to show the correct conversions.  Cannot guarantee it is what they wanted though.  But I feel happier for having tried.  smile

Bob

View Image: zeef6.GIF

Last edited by bob bundy (2011-07-07 06:23:49)


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#107 2011-07-12 06:38:34

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: Exponents and Scientific Notation

yeah my algebra lessons are really hard i give up sometimezzz thanx for clearing these out



ps.   are 14-e and 17 19 20 are all incorrect?


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#108 2011-07-12 08:09:58

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,473

Re: Exponents and Scientific Notation

Hi zee-f;

Could you please recopy the questions you are having a problem with? This, way people can see them.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#109 2011-07-12 09:07:01

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: Exponents and Scientific Notation

yup sure
19. Estimate the amount of juice in a typical orange juice carton in liters.
Aabout 8 liters
Babout 5 liters
Cabout 4 liters
Dabout 3.5 liters
Eabout 2 liters
Fabout .5 liters


20. Estimate the weight of a small can of soup in grams.
Aabout 30 grams
Babout 500 grams
Cabout 250 grams
Dabout 325 grams
Eabout 750 grams
Fabout 100 grams


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#110 2011-07-12 09:08:35

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: Exponents and Scientific Notation

and i need help to explain my new answer for 17 and 14 like am confused i need an explanation


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#111 2011-07-12 09:39:52

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,473

Re: Exponents and Scientific Notation

Let's start with 14 first, which makes sense. Please recopy your work right here.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#112 2011-07-12 09:50:55

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: Exponents and Scientific Notation

ok so for 14 3.25 k =3250000 so my mistake is in the second caulm why???


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#113 2011-07-12 09:56:21

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,473

Re: Exponents and Scientific Notation

Every gram is made up of 1000 milligrams.

3.25 kilograms is equal to 3250 grams. Each of them is made up of 1000 milligrams, so there are

3250 * 1000 = 3 250 000 milligrams


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Online

#114 2011-07-12 09:57:33

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: Exponents and Scientific Notation

yup i get that point but like in the picture why is the mistake in the second calum ?


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#115 2011-07-12 09:58:17

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,473

Re: Exponents and Scientific Notation

That is the problem I do not know where the picture is. It is lost in a zillion posts.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Online

#116 2011-07-12 10:01:44

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: Exponents and Scientific Notation

oooh ok hhhhh ill post it right now


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#117 2011-07-12 10:03:19

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,473

Re: Exponents and Scientific Notation

Okay, remember time is money.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Online

#118 2011-07-12 10:04:41

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: Exponents and Scientific Notation

smile heres the pic

View Image: test14.jpg

One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#119 2011-07-12 10:06:53

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,473

Re: Exponents and Scientific Notation

That was quick, very good. What is wrong with column two?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Online

#120 2011-07-12 10:08:34

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: Exponents and Scientific Notation

there spouse to multiply it by 1000? i dont know thats what am reaalllllly confused at


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#121 2011-07-12 10:11:42

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,473

Re: Exponents and Scientific Notation

The chart says 1 kilogram = 1000 grams. (kilo means 1000).

So to get the number of grams from 3.25 kilograms you would multiply 3.25 kilograms x 1000 = 3250 grams


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Online

#122 2011-07-12 10:22:47

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: Exponents and Scientific Notation

ok so what they did incorrect is multiplied or put 1 kg in the second column and there spouse to put 1000 like multiply it by a 1000 right ?


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#123 2011-07-12 10:29:19

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,473

Re: Exponents and Scientific Notation

Yes, the calculation is

3.25 x 1000 x 1000 = 3.25 x 1000000 = 3 250 000

Where did she go?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Online

#124 2011-07-12 19:48:09

bob bundy
Moderator
Registered: 2010-06-20
Posts: 6,528

Re: Exponents and Scientific Notation

hi bobbym,

I think the instructions specify a certain layout for doing the conversion.  See my diagram in post #104.

I'm guessing that: when the conversion requires a 'multiply' , the factor is put on the top line, and when the conversion requires a 'divide' the factor is put on the bottom.

So the first error occurs because the conversion is shown up-side-down, leading to a second error where the original measurement is divided by 1000 when it should be multiplied.

zee-f correctly did the conversion, so only got the wrong multi-choice answer because of the layout requirement.  Maybe she was given instruction on this.  In which case it would help to see it.

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#125 2011-07-12 19:52:06

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,473

Re: Exponents and Scientific Notation

Hi Bob;

I see that she had it explained to her already. I think that she is a little shaken over it.  Maybe she got it, I do not know.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Online

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