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Here's one more question I need help with.

Samir has some amount of rupees with him, the difference between $45.45$% and 36.36% of which is Rs. $789435689$. Find the amount.

a) $8683792579$

b) $8673792579$

c) $7573781479$

d) $88667292579$

e) None of these

Now, Samir is the name of Indian male, rupees is Indian currency and Rs. is symbol for Indian currency. You can try replacing those with and question will be the same. :)

Here's what I've done. I've subtracted 45.45$%-$36.36$%=$9.09$. I've multiplied $789435689*9.09/100. Which should be answer, but it isn't and I don't know why. Am I doing something wrong?

The actual answer is a) 8683792579$.

Can anyone elaborate how its a) and if not, my method is correct or not?

Thanks in advance and really sorry for asking too many stupid questions. :(

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    I'm not sure if double commenting is allowed or not, but last comment already exceeded the amount of characters, so I'm writing this one. Btw, is it okay if I ask such questions here? I mean I don't really wanna get banned for asking stupid questions. Kindly slap me whenever I'm asking idiotic questions. Thanks, I really appreciate your support guys. You've just made my day! (Night actually) :P2010-08-26

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789435689 is 9.09% or 9.09/100 of the whole amount—that is, $789435689=\frac{9.09}{100}x$ where $x$ is the whole amount—so you want to divide by 9.09/100 rather than multiplying by it.

It also may be worth noting that $0.\overline{36}=\frac{4}{11}$ and $0.\overline{45}=\frac{5}{11}$, so $0.\overline{09}=\frac{1}{11}$, so you are essentially multiplying by 11, which can be done by multiplying by 10 and adding the original number or by writing two copies of the number, shifted one place, and adding:

   789435689 + 789435689 ------------ 
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    Ohh, thanks for pointing that out and stating it in the form of equation. I feel idiot for hurrying things even though I knew it has something to do with the 1/11 value being 9.09. Sorry, I confused it with multiplication instead of actually doing division. Sorry for all the trouble you have to go through because of me.2010-08-26