The weekly sales in thousands of items of a product has a seasonal sales record approximated by n = 84.59 + 24.8 sin πt/24 (t is time in weeks with t = 1 referring to the first week in the year). During which week(s) will the sales equal 96,990 items?

A. week 4, week 20, and week 52
B. week 21 and week 30
C. week 4 and week 47
D. week 30 and week 47

Question

The weekly sales in thousands of items of a product has a seasonal sales record approximated by n = 84.59 + 24.8 sin πt/24 (t is time in weeks with t = 1 referring to the first week in the year). During which week(s) will the sales equal 96,990 items?

A. week 4, week 20, and week 52	
B. week 21 and week 30	
C. week 4 and week 47	
D. week 30 and week 47

anonymous · Answer

(96.990 - 84.59)/24.8    =   sin (t)(pi)/24    =   0.5

This happens at t = 4, 20, and 52    because those values will correspond to:

sin pi/6,       sin 5(pi)/6,      sin pi/6

anonymous · Answer

All good now, @Girl_Ninja ?

anonymous · Answer

oh okay yes @tcarroll010 thank you ;-)

anonymous · Answer

You're welcome!  Good luck in all of your studies and thx for the recognition! @Girl_Ninja