If m and r are 2 numbers on a number line, what is the value

Question

If m and r are 2 numbers on a number line, what is the value of r?
1/ the distance between r and 0 is 3 times the distance between m and 0

2/ 12 is half way between m and r.

Please explain how you come up with the answer.


Thanks a bunch!!

anindyat · Answer

Going for E
We donâ€™t know the sign of the numbers...More than one solution possible...

jfd1244 · Answer

I was going to say C....when m=6 and r=18 both conditions one and two are satisfied...

Fig · Answer

(E) as well

From 1 |r| = 3*|m| : as a distance is always positive and m & r could be negative, we have to use the absolute value. As well, we can do nothing to know r. INSUFF. From 2 (r+m)/2 = 12 <=> r = 24 - m : an equation with infinite possibilities for the couple (r,m) INSUFF. Combining 1 with 2 |r| = 3*|m| o If r=3*(-m), then -3*m = 24 - m <=> 2*m = -24 <=> m = -12 and so, r = 36 o If r=3*(m), then 3*m = 24 - m <=> 4*m = 24 <=> m = 6 and so, r = 18 We remain with 2 possible value of r. INSUFF.

asaf · Answer

If m and r are 2 numbers on a number line, what is the value of r? 

1/ the distance between r and 0 is 3 times the distance between m and 0 

2/ 12 is half way between m and r. 

1) r = 3*m . Insufficient.
2) Insufficient

Combining:

If 12 is the mid-point then m=6, r=18?


C.

MBAlad · Answer

I see E now but would've gone for C I reckon - D'oh

enola · Answer

Thank you very much for all of your explanations !!

OA is E

If m and r are 2 numbers on a number line, what is the value

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