Question

3. The Windless Surfing Company has determined its cost for making custom sails to be C = 380 + 18S, where C is the cost in dollars, and S is the number of sails. If the cost can be higher than $4,000 but must be smaller than $11,000, how many sails can they make per week? (You must set up an inequality.)

Answer 1

The cost equation is:

`C=380+18S`

This cost has to be between 4000 and 11,000. Thus, we can write:

`4000<380+18S<11000`

We can solve for the range of S with a little algebra, shown below:

[tex]\begin{gathered} 4000<380+18S<11000 \\ -380<-380<-380 \\ ---------------- \\ 3620<18S<10620 \\ \frac{3620}{18}<\frac{18S}{18}<\frac{10620}{18} \\ 201.11To meet the needs, the Windless Surfing Company can make between 202 sails and 589 sails.