Solve rpm in rotational motion problem

1. Homework Statement
How fast (in rpm) must a centrifuge rotate if a particle 7.0 cm from the axis of rotation is to experience an acceleration of 100,000 g's?

My variables
radius= 7 cm or .07m
radial accel= 100,000 g's or 980,000m/s^2 or 98,000,000cm/s^2
V= I think I need this to get w
w= ? I think I need to solve this to get rpm
rpm= ? this is what I want

2. Homework Equations
radial accel = v^2/r
v= rw

3. The Attempt at a Solution
980000/.07 = 68,600

$$\sqrt{}68600$$/.07= 261.9
261.9/.07 = 3,741 rpm

whether i set everything as meter or centimeter, I still get the same answer. I check the back of the book and it says 3.6x10^4 or 36,000rpm
1. Homework Statement

Any help would be appreciated.

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