Algebra Problem

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Algebra Problem

by anwarma » Wed Jun 11, 2008 4:30 pm
On a certain scale of intensity, each increment of 10 in magnitude represents a tenfold increase in intensity. On this scale, an intensity corresponding to a magnitude of 165 is how many times an intensity corresponding to a magnitude of 125?

(A) 40
(B) 100
(C) 400
(D) 1,000
(E) 10,000

ANS is E
I guess I am having trouble understanding the the setup, can someone help?
AA

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by AleksandrM » Wed Jun 11, 2008 6:03 pm
If each increment of 10 in magnitude represents a tenfold increase in intensity, then:

165 - 125 = 40

10^4 = 10,000

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by durgesh79 » Wed Jun 11, 2008 10:24 pm
an alternate way to understand.

value - intensity
125 - X
135 - 10X
145 - 100X
155 - 1000X
165 - 10000X

Answer = 10000x/x = 10000