please don't ask 2 questions in 1 question
remember that percent is parts out of 100 so x%=x/100
basically just remove the percent sign and move the decimal place 2 places to the left to convert to fraction
the first one
20 dollars
4.75% tax
15% tip
it depends if you want to tip on the total with tax or without tax
it is better to top on the without-tax value since tax comes from you so
find 4.75% of 20 and add that to 15% of 20 then add that to 20 to get the proper value
scenarios
1. 20+(20 times 4.75%)+(20 times 15%)=23.95
2. ([(20 times 104.75%)] times 115%)=24.09
both are bellow $25 so $25 shoudl be enough to cover it
total cost of a spa treatment of 42 with 6% tax and 20% tip
so you could again do two things:
1. apply tax and give tip on the new amount
2. find the tip and add that to the tax of only 42
scenarios:
1.(42 times 106%) times 120%=$50.4
2. (42 times 20%) +(42 times 106%)=$52.92
it depens on what you tip on