5^21 x 4^11 = 2 x 10^n
n=?
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daretodream
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harsh.champ
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R.H.S.= (2) x (2)^n x (5)^ndaretodream wrote:5^21 x 4^11 = 2 x 10^n
n=?
=[(2)^(n+1)] x 5^n
L.H.S. = 5^21 X 2^22
So, comparing exponents we get n=21
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ajith
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5^21*4^11 = 2*10^ndaretodream wrote:5^21 x 4^11 = 2 x 10^n
n=?
5^21* (2^2)^11 = 2*10^n
5^21* 2^22 = 2*10^n
2* (5^21* 2^21) = 2*10^n
2* (5*2)^21 =2*10^n
2* (10)^21 =2*10^n
n =21
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shashank.ism
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5^21 x 4^11 = 2 x 10^ndaretodream wrote:5^21 x 4^11 = 2 x 10^n
n=?
It is simple question of equation powers of similar base as discussed in some earlier post
--> 5^21 x 2^22 = 2 x (5x2)^n
--> 5^21 x 2^22 = 2^(n+1) x 5^n
[spoiler]so n = 21 ans[/spoiler]
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thephoenix
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LHS=5^21 * 2^22daretodream wrote:5^21 x 4^11 = 2 x 10^n
n=?
RHS=2*(2*50)^n=2^(n+1) * 5^n
when LHS=RHS----> n=21
