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Expert: - 6/10/2009


Question
QUESTION: can you solve this problem

         n^2*5
fraction bar> ----->9.5
         5^2

ANSWER: I'm not sure exactly on the problem, since this langue does not translate multiple line correctly.  The n is over 'bar' and the 5 is under '>'.  A better way to state this would be 5n^2/5^2 or 5n²/5²,
if that is what the problem is.  Now am I suppose to find the value that would make this equal to 9.5?

If that is that case, multiply both sides by 25, since that is 5².
That makes the equation 5n² = 225 + 12.5 = 237.5.

Divide by the 5, getting n² = 47.5.  That should gives us
n a little less than 6.9, since 6.9² = 4.761.  
As it turns out in Excel, the answer is 6.892024376.

If the question is not 5n²/5² = 9.5, you could highlight the equation I just gave you, correct it, and ask me again.



---------- FOLLOW-UP ----------

QUESTION: the correct problem is n^2 * 5/5^2 >9.8

I made some mistakes on the last email. I was typing on my phone.

ANSWER: The last problem had what I thought was a typo,
and you just clarified it to make sure my assumptions were correct.

The 5 over 5^2 cancels for sure to 1/5,
so the problem is definitely x² / 5 > 9.8,
so my answer was correct.

Thank you for the clarification, so now I'll stop wondering about it.


---------- FOLLOW-UP ----------

QUESTION: the answer is 7.4
I can't figure out how
I'm using software called excel at math. In the practice section, this is one of the problems. and it gave 7.4 as the  answer.

Answer
I put 7   in Excel, and I got 9.8.
The formula I used was putting a 7 in A1 and
putting a =A1^2*5/5^2 in B1.
What I got was 9.8 in B1.

What formula did you put in?

If that is not the right equation?

In an education book for a math student,
I don't see how they got an answer of 7.4
when 7 is a lot simpler to see.

We can both see that 9.8 * 5 = 49, which is 7².

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