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* nbme 4 block 3 q 15
 #509995  
  formle99 - 05/31/10 11:31
 
  A dilute disinfectant kills 90% of bacterial inoculum in 10 minutes.which of the following is the shortest amount of time(in minutes) required to reduce an amount of inoculum to 10 bacteria?
a.10
b.50
c.100
d.140
e.180
 
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* Re:nbme 4 block 3 q 15
#2118384
  formle99 - 05/31/10 11:42
 
  any kind soul please explain this question  
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* Re:nbme 4 block 3 q 15
#2118388
  formle99 - 05/31/10 11:46
 
  sorry some mistake in question
a dilute disinfectant kills 90% of bacterial inoculum in 10 minutes .which of the following is the shortest amount of tiime (in minutes ) required to reduce an inoculum of 10^9 bacteria to less than 10 bacteria
A.10
b.50
c.100
d.140
e.180
 
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* Re:nbme 4 block 3 q 15
#2118403
  basicq - 05/31/10 12:34
 
  In every 10 mints 90% are killed so after every 10 mints we are left with 10%

now lets apply

10^9 =1000.000.000 and 10% of it will be 10^8

0mint ---------10^9
10mint -------- 10^8
20mint-----------10^7
30mint-------------10^6
40mint-----------------10^5
50mint-------------------10^4
60mint----------------------10^3
70mint------------------------10^2
80mint-----------------------------10^1
90mint -----------------------------less than 10

so answer cc
 
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* Re:nbme 4 block 3 q 15
#2845516
  metoprolol - 03/06/13 21:43
 
  Hi,

Greetings to all

I am a new guy to this web-world, got scheduled to take step 1 on march 21, 2013

What should I do during this period for best outcome?

appreciation and thnx in advance
 
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