Answer:
a) $8018.78
b) $8056.60
c) 8540 / (1+r)
d) r = (8540/x) - 1 where "x" is the list price.
Step-by-step explanation:
Recall that the:
total price paid = list price + sales tax
total price paid = list price + percent * list price
a) then, in Washington:
8540 = x + 0.065 * x
8540 = x (1 + 0.065)
8540 = x (1.065)
x = 8540 / 1.065
x = $8018.78
b) in Idaho where the sales tax is 6.0% we do a similar calculation but using the decimal form of the percent 0.06:
8540 = x (1 + 0.06)
8540 = x (1.06)
x = 8540 / 1.06
x = $8056.60
c) If the percent tax is "r" then:
we do:
8540 = x (1+r)
x = 8540 / (1+r)
d) solving for "r" instead of for "x":
8540 = x (1+r)
divide by "x" (the list price):
(8540/x) = 1 + r
subtract 1 from both sides:
(8540/x) - 1 = r
