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moneyman
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PostPosted: Sat Sep 01, 2007 5:44 am    Post subject: Testprep1 Reply with quote
If 5^21*4^11=2*10^n , what is the value of n??

11
21
22
23
32
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agps
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PostPosted: Sat Sep 01, 2007 6:22 am    Post subject: Reply with quote
we start with
5^21*4^11=2*10^n
5^10*5^11*4^11=2*10^n
5^10*20^11=2*10^n
5^10*20^10*20=2*10^n
100^10*20=2*10^n
10^10*10^10*2*10=2*10^n
2*10^21=2*10^n
n=21
Answer B
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moneyman
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PostPosted: Sat Sep 01, 2007 11:24 pm    Post subject: Reply with quote
OA is B...Thanks for explaining in an easier way
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