Uncertainty for a ratio ( help)

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To find the uncertainty in the ratio of the diameter to the thickness of the cookies, the key is to apply the calculus error propagation method. The ratio is expressed as d/h, where d is the diameter and h is the thickness. The uncertainty in this ratio can be calculated using partial derivatives, specifically by taking the derivative of the ratio with respect to each variable and applying the uncertainties. The initial ratio is given as 89.5, and the discussion highlights the confusion around using the negative exponent for division. Ultimately, the user resolved their frustration and figured out the problem independently.
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Uncertainty for a ratio (urgent help!)

Question: As you eat your way through a bag of chocolate chip cookies, you observe that each cookie is a circular disk with a diameter of d = 8.32 cm +/-1×10−2 cm and a thickness of h = 9.3×10−2 cm +/-1×10−3 cm.
Find the uncertainty in this ratio of the diameter to the thickness.

Hint:Notice the division.
If we are dividing that is a negative exponent.

The ratio of the diameter to the thickness is 89.5. How can I use the calculus error prop./the partial derivative to solve this? The hint also made things more confusing.
Someone said to said it up like this or something: d*h^-1, but I still don't understand.
Plus, I don't see how you can get a ratio from the partial derivative formula. And I tried manipulating the volume formula: v=[(pi d^2)/4]*h, but it can't go to d/h...I was spending my time yesterday and today just to solve this problem and I couldn't figure it out and it was the only problem I had trouble with...sorry I'm very frusterated right now >:[
 
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nevermind I figured it out :)
 
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