What are the rules wrt. sig figs when multiplying or dividing a number with an uncertainty and an exact number?

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The answer sheet for my math book is full of errors and the book does not explain this concept at all. According to it :

(28,3 ± 0,05) x 4 = 113,2 ± 0,2

So one sig fig is added to the value and one is removed from the uncertainty.

(28,3 ± 0,05) ÷ 4 = 7,075 ± 0,0125 rounded to 7,08 ± 0,01

Here the number of sig figs for both the value and the uncertainty is maintained, but the value is rounded to one more decimal place.

I am confused as to what the rules are supposed to be here.

Thank you for your help.