Dimensional Analysis (chemistry Homework)?

There is missing information in the question. "How many inches are in 3.25 x 10^4 " 3.25 x 10^4 of What? what are the units?

Anyway, For dimensional analysis start off with the number they give you: 3.25 x10^4.

You always want to convert from one unit of measurement to another (in this case from ______ to inches).

THerefore, you always try to cancel out the units from left to right by "dividing them". (4/5) * (1/4) is 1/4 because you canceled out the 4. Dimensional Analysis follows the same idea. You use conversion factors (basically ratios) to cancel out the given units to what you are trying to find.

Example. If the question were 3.25x10^4 yards, here's what you would do:

(3.25x10^4 yards) x (3 feet / 1 yard) x (12 inches / 1 feet). [if you write that out on paper, you can see that you could cancel out yards, and feet, leaving you with inches only in the numerator.

multiply them like you would multiply fractions. you have your answer.

Why did I use 3 feet / 1 yard? I wanted yards in the denominator so I could cancel out yards. And, there are 3 feet in a yard.

Hope this helps.