A$78.00 pair of shoes cost $84.63 after tax is added. what percentage of the cost is tax?
a) 8.0%
b) 8.25%
c) 8.5%
d) 8.75%

C) 8.5%

Step-by-step explanation:

First, subtract the cost after tax to the cost before tax.

84.63 - 78.00 =

6.63

Then, divide the original cost from this

6.63 / 78.00 =

0.085

When reading percentages on a calculator, we know this is equivalent to 8.5%

Hope this helps! :)

1 number

if we use a graphing calculator, there is only one such number that satisfies the conclusion of the mean value theorem, that is, a number such that

where the right-hand side is the average rate of change of f on the interval [0.5,0.75], which is the slope of the secant line.

in the attached graph, the black line is the secant line which has its slope as the average rate of change of f on [0.5,0.75], while the orange line is the only tangent line to the graph of f in the interval that satisfies the mvt conclusion.