SOLUTION: If (2rs)^-1 = 3s^-2, what is the value of r/s ?

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Question 1105177: If (2rs)^-1 = 3s^-2, what is the value of r/s ?
Found 2 solutions by Boreal, greenestamps:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
This is 1/(2rs)=3/s^2
Therefore, s^2/2rs=3
s/2r=3
s/r=6
Check using s=12 and r=2
(48)^-1=3/144, and both are 1/48.

Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


1%2F%282rs%29+=+3%2Fs%5E2
"cross multiply": s%5E2+=+6rs
Get r/s on the right side by dividing both sides by 6s^2:
s%5E2%2F%286s%5E2%29+=+%286rs%29%2F%286s%5E2%29
1%2F6+=+r%2Fs

r/s = 1/6