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by kishore » Sat Jun 21, 2008 6:22 pm
Ans) n = 21

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

5 ^ 21 * (2^2)^11 = 2 * 10 ^ n

5 ^ 21 * 2^22 = 2 * 10 ^ n

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

5 ^ 21 * 2^11 can be written as 10 ^ 21

2 * 10 ^ 21 = 2 * 10 ^ n

=> n = 21
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by Nycgrl » Sat Jun 21, 2008 7:42 pm
kishore wrote:Ans) n = 21

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

5 ^ 21 * (2^2)^11 = 2 * 10 ^ n

5 ^ 21 * 2^22 = 2 * 10 ^ n

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

5 ^ 21 * 2^11 can be written as 10 ^ 21

2 * 10 ^ 21 = 2 * 10 ^ n


Kishore can you please explain 5 ^ 21 * 2^11 can be written as 10 ^ 21


Thanks

=> n = 21
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by rosh26 » Sat Jun 21, 2008 7:44 pm
Hi Kishore, thanks for the reply.

Can you elaborate furthur on this detail??

5 ^ 21 * 2^11 can be written as 10 ^ 21

Thanks.
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by atlantic » Sun Jun 22, 2008 10:14 am
(5^21)*(4^11)=2*(10^n)

(5^21)*(2^22)=2*(10^n)

(5^21)*(2^21)*2=2*(10^n)

(5^21)*(2^21)=10^n

10^21=10^n

n=21

Let me know if you miss something
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