5^21 * 4^11 = 2*10^n

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5^21 * 4^11 = 2*10^n

by sanju09 » Wed Apr 08, 2009 5:31 am
If 5^21 * 4^11 = 2*10^n, what is the value of n?
A. 11
B. 21
C. 22
D. 23
E. 32


OA B
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by sacx » Wed Apr 08, 2009 5:33 am
5^21 * 2^22 = 2*10^n
2*10^21 = 2*10^n

10^21 = 10^n

n = 21
SACX