Question

One uranium atom has a diameter of 3.5×10−8

centimeters. What is the sum of 1,000,000 uranium atoms’ diameters, in centimeters, written in standard notation?

A.) 3.5
B.) 0.35
C.) 0.035
D.) 0.0035

Answer 1

The first trick is to know that adding something 1,000,000 times is the same as 1,000,000 times that number.

So, you're really asked to do 1000000 x 3.5x10^-8.

Well, 1000000 = 10^6, so we can rewrite that as:

10^6 x 3.5x10^-8

And that equals 3.5 x 10^-2.

Written in stanrd notation, that'd be 0.035.

Answer: C