The practical rule would be, times that number, by the result of the first time you multiplied the first number. But, it would all depend by how much your're raising the number by.
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For example:</u>

We do,

But, once again, this was an example. This would show and illustrate the rule of "raising a power".<span />
True, because 4.2 is a lot lower than 55.3, 73.4, 89.3, and 132.2.
Answer:
98 - 84 = 14(this is the change) now we convert this to a percent
14/1 x 100/100 = 14%
70% of the Jerseys are medium-sized.
If you wanna know how I got my answer then just ask. :)
Hope this helped!