First you would take 20% off the orignal price giving you 30.4$ after that you take 10% of 30.4 to get 27.36$.
The second one if im not wrong
SO what you need to do is:
<span>Start with |f(x) - 3| < 0.4
and plug in f(x) = x+1
to get
|f(x) – 3| < 0.4
|x+1 – 3| < 0.4
|x - 2| < 0.4
-0.4 < x - 2 < 0.4
-0.4+2 < x < 0.4+2
1.6 < x < 2.4
So delta would be 2.3
Hope this is what you were looking for
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