Pls help as soon as possible the second variable is positive or negative

Isee the amount was $90.00 then reduced to $75.00 , what is the percent ?

The median of a data set is the measure of center that is found by adding the data values and dividing the total by the number of data values that is the value that occurs with the greatest frequency that is the value midway between the maximum and minimum values in the original data set that is the middle value when the original data values are arranged in order of increasing (or decreasing) magnitude

Eden has a part time job. she is paid ? 7.20 an hour the week she worked 18 and a half hours how much is she paid