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by DanaJ » Sat Feb 28, 2009 4:22 am
This question has been answered many times before. But there goes:
The equation provided is equivalent to (5^m)*(4^18) = 2*10^35, since all I did was "flip" the whole thing (the numerator is 1 on both sides).
Now, look at 4^18: it's actually (2^2)^18 or 2^(2*18) or 2^36.
10 = 2*5, so you get that 10^35 = (2*5)^35 = (2^35)*(5^35). Notice that 2*10^35 = 2*(2^35)*(5^35) = (2^36)*(5^35)

Replace these in the initial equation and you get that:
(5^m)*2^36 = (2^36)*(5^35). From this m is 35.
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by Uri » Sun Mar 01, 2009 6:07 am
DanaJ wrote:This question has been answered many times before. But there goes:
The equation provided is equivalent to (5^m)*(4^18) = 2*10^35, since all I did was "flip" the whole thing (the numerator is 1 on both sides).
Now, look at 4^18: it's actually (2^2)^18 or 2^(2*18) or 2^36.
10 = 2*5, so you get that 10^35 = (2*5)^35 = (2^35)*(5^35). Notice that 2*10^35 = 2*(2^35)*(5^35) = (2^36)*(5^35)

Replace these in the initial equation and you get that:
(5^m)*2^36 = (2^36)*(5^35). From this m is 35.
Dana, I am getting m= -35. could you please check the answer once again?
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by DanaJ » Sun Mar 01, 2009 6:31 am
You may be getting -35 because of the way sudi760mba wrote the equation. The correct version is, I believe:
[(1/5)^m] * [(1/4)^18] = {1/[2(10)]}^35
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by Uri » Sun Mar 01, 2009 11:34 am
thank you, Dana! that was the reason.
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by welcome » Mon Mar 02, 2009 1:30 am
(1/5)^m (1/4)^18 = 1/2(10)^35
Shold be like

(1/5)^m (1/4)^18 = {1/2(10)}^35

Now solve it, you will get m=35
Shubham.
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by Uri » Mon Mar 02, 2009 1:32 am
thank you, shubham! i've got it.
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