7.35 x 10^-6 cm per second
This is an exercise in division using scientific notation. So
6.35x10^-1 / 8.64x10^4 = ?
To perform division using scientific notation, you divide the significands as you would normally. So
6.35 / 8.64 = 0.734953704
Then you subtract the exponents. So
-1 - 4 = -5
Giving you a result of
0.734953704 x 10^-5
Notice that the significand in this case is less than 1. That means that you now need to normalize the result, getting a significand that's greater than or equal to 1 and less than 10. We can do this by multiplying the significand by 10 and then subtracting 1 from the exponent. So
0.734953704 * 10 = 7.34953704
-5 - 1 = -6
Giving a new result of:
7.34953704 x 10^-6
And don't forget about significant figures. Since the least precise piece of data we have is 3 digits, we should round the result to 3 digits. So the final answer is 7.35 x 10^-6 cm per second.
