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kpkanupriyakhmi
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Algebra Book, pg 89, q27 and pg 155, q12 - GT issues + Varia

by kpkanupriyakhmi Sat Feb 28, 2015 8:27 am

1. Q 27, didn't understand the criteria GT(negative value)*GT(negative value)= LT(positive value)
2. Q12:- didn't understand how to do by variables?
tommywallach
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RE: Algebra Book, pg 89, q27 and pg 155, q12 - GT issues

by tommywallach Sun Mar 01, 2015 8:59 pm

Hey KP,

Please, in the future, post ONE question per thread. Also, try to give slightly more description of where you went wrong. Helpful to start off my explaining what you did.

1. Just test numbers so you can see it.

GT(-2) * GT(-2) --> -1.9 * -1.9 = 3.61 (i.e LT 4)

2. I don't actually have a standard paginated book (I use an online ebook), so I actually need more. Please say the chapter number and question number, as well as a bit of text from the question (you could also post the whole question, if it isn't too long, so that this thread becomes useful for others as well).

Thanks!

-t
kpkanupriyakhmi
Students
 
Posts: 48
Joined: Sat Jul 12, 2014 5:57 am
 

Re: Algebra Book, pg 89, q27 and pg 155, q12 - GT issues + Varia

by kpkanupriyakhmi Wed Mar 04, 2015 6:01 am

1.In Q1 I didn't get the solution given at the back on page number 95(i.e. Q27 Pg 89, book 1)
2.Chapter number 7 Q 12"If the total weight of the pumpkin....."??
tommywallach
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Re: Algebra Book, pg 89, q27 and pg 155, q12 - GT issues + Varia

by tommywallach Sun Mar 08, 2015 9:05 pm

1. I explained what you should do on this. Just look at numbers. If the explanation doesn't make sense, don't worry about it.

2. Total weight = # of pumpkins * average weight of pumpkin

Let's put that in variables:

T = N * A

And solve to the average:

T/N = A

Now, we know the Total weight is going up by a factor of 10, and the number of pumpkins is going down by 20%:

10T = .8N * New Average

Now let's solve to our new average:

100T = 8N * New Average

100/8 * T/N = New Average

100/8 = 12.5

So the old average was T/N

The new average is 12.5 * T/N.

So the answer is (E).

-t