Please help ;-(

G

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Write answers in scientific notation. Round to three decimals.

(5.36*10^4)+(3.55*10^-5)

Thanks to the answers in the back of the book, I know that the solution is 5.715*10^-4

I understand the 5.715 and I got that by multiplying 5.36*10^4 and 3.55*10^-5 and adding those answers, however, I don't understand how the solution involves 10^-4
 
Hello blessedone:

You better check what you typed or look at your book more closely because the answer which you say is in your book is not correct for the addition of those two numbers.

5.36 x 10^4 = 53600

3.55 x 10^(-5) = 0.0000355

Adding these gives us:

53600.0000355

which we would write as:

5.36000000355 x 10^4

~ Mark
 
Thanks Mark, I did write the problem wrong. It's actually:

(5.36*10^-4)
 
Okay -- Thanks For Clarifying.

Hello blessedone:

I'll show you why we need the 10^(-4) after I add the numbers.

5.36 * 10^(-4) = 0.000536

3.55 * 10^(-5) = 0.0000355

Adding these two numbers gives us 0.0005715

We are told to write this result using scientific notation. This means that we need to write a number from 1.0 up to (but not including) 10.0 and then multiply it by an appropriate power of ten to move the decimal point to the proper location.

So, the number from 1.0 up to (but not including) 10.0 is:

5.715

The value that we are trying to express has the decimal point moved four places to the left. That is why we need the factor of 10^(-4). Multiplying by a power of ten -- when the exponent is negative -- moves the decimal point to the left. So, multiplying by 10^(-4) moves it four places to the left. This is what we want.

5.715 * 10^(-4) = 0.0005715

Let us know if you need more help with this question.

~ Mark
 
THANKS A MILLION!!!! :D With your help and the help of my 14y.o. daughter, I got it!!!! I'm sure I'll be back soon :wink:

Yolanda
 
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