Question

The weekly sales in thousands of items of a product has a seasonal sales record approximated by n=60.31+19.4sin(/24) (pi x t /24) (t is time in weeks with t=1 referring to the first week in a year.) During which week(s) will the sales equal 70,010 items? Show your work.

Answer 1

We are given with the equation
n = 60.31 + 19.4 sin (πt/24)
where n is the weekly sales in thousands of item
and t is the time in weeks

The week that will result to a sales of 70,010 is
70.01 = 60.31 + 19.4 sin (πt/24)
t = 4
weeks from the first week