By getting a discount of 20%, it means he pays 100-20=80% of the initial price
80% is same as 0.8
Price after discount will be
0.8*$562=$449.6
Taxation is then subjected to the discounted price. With tax rate of 6% which is equivalent to 0.06 then the total prive incurres will be 106% of the discounted price, same as 1.06
Final price inclusive of tax
1.06*$449.6=$476.576
Since his credit gives 2% discount of everytging then he only pays 98% of the price inclusive of tax
