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abey_27
Oct29-08, 04:41 AM
7 × 10^6 divided by a × 10^n is equal to 8.75 × 10^9

a is greater or equal to 1 but less than 10. n is an integer.

Find the value of a and the value of n.
I do not really understand how to separate the a and n, and thus find a value for each of them. Some help would be highly appreciated.


thanks integral, but how exactly does that help??

Remember:

\frac {a b} {c d} = \frac a c . \frac b d

Ertosthnes
Oct29-08, 05:20 AM
It's easier if you don't think about the algebra. Set up the equation like this:

\frac{7*10^6}{a*10^n}=\frac{7}{8}*10^10

Hopefully it's obvious that 8.75*10^9 = (7/8)*10^10.

From there you can just sort of see the numbers that will work.

Integral
Oct29-08, 05:42 AM
Your problem is

\frac {7 x 10^6} {a x 10^n} = 8.75 x 10^9

You can't see that this is the same form as the fraction in my first post?