Answer: the final price is $37.26
Explanation:
Always when we have an increase in a percentage X%, with an initial amount A, the new amount will be:
A + A*(X%/100%)
And for a decrease, the equation is_
A - A*(X%/100%)
Then if the initial price is $49.76, and there is a decrease of the 30%, the new price will be
$49.75 - (30%/100%)*$49.75 = $34.83
Now we have an increase of the 7% because of the IVA, then the final price is:
$34.83 + (7%/100%)*$34.83 = $37.26