how do you find ...weekly sales in thousands of items of a product has a seasonal sales record approximated by y=18.1sin(piex/24)+52.9 where x is time in weeks and 1 is the first week in janurary. during which weeks will the sales equal 61,950 items this year? list all the weeks...

Answer 1

evaluate y for x from 1 to 52 (weeks).
For example, for the first week, x=1,
so
y=18.1*sin(π*1/24)+52.9=55.26
Do it for all 52 weeks, plot it if possible.
Since the maximum over the year is around y=70, I suppose the sales of 61,950 means 61.950 where the "," is used as a decimal point in many countries.