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Videoorchard
Prospective Students
 
Posts: 48
Joined: Thu Mar 06, 2014 2:58 am
 

Number Properties

by Videoorchard Sun Apr 06, 2014 12:26 pm

Hi,

I have a question regarding Number Lines chapter of the number properties. I.e Regarding the problem set section of the number lines (question 10).

Question:
The Question states that, S is the midpoint of QR,r=-2q and we are asked to compare between two quantitys. Quantity A i.e S and Quantity B i.e 0.

Approach:
Now,The way i have approched the problem is, i considered value of q=1,and according to the equation stated above,r should be twice the value of q and should be negative i.e r=-2 ,now when i tried solving it this way,i get the value for midpoint as s=-0.5 ((-2+1)/2=-0.5).hence 0>-0.5..which seems to be the wrong answer..the right answer is Quantity A

sir,could you kindly please look into this problem and tell me and kindly elucidate the answer

Regards,
Manish A.
tommywallach
Manhattan Prep Staff
 
Posts: 1917
Joined: Thu Mar 31, 2011 11:18 am
 

Re: Number Properties

by tommywallach Wed Apr 09, 2014 9:49 pm

Hey Manish,

You forgot that q is to the left of r on the number line, which means q has to be smaller than r. You can't plug in 1 for q, because that would make r = -2, which would make r smaller than q.

Hope that helps!

-t