Answer:
(1) C (24, 12) = $13,720
(2) C (70, 7) = $23,110
(3) C (30, 30) = $21,100
Explanation:
The monthly cost function for the production of two models of a surfboard, a standard model and a competition model is:
![C(x,\ y)=4000+240x+330y](https://img.qammunity.org/2021/formulas/mathematics/college/jq8jw0usj4wcr4vdsc0gftxbusohbhy20y.png)
Here,
x = number of standard model surfboard produced per month
y = number of competition model surfboard produced per month
(1)
Compute the value of C (24, 12) as follows:
![C(x,\ y)=4000+240x+330y](https://img.qammunity.org/2021/formulas/mathematics/college/jq8jw0usj4wcr4vdsc0gftxbusohbhy20y.png)
![C(24,\ 12)=4000+(240 \cdot24)+ (330\cdot12)](https://img.qammunity.org/2021/formulas/mathematics/college/ey8n4acq58zze540z7go0o93db7enlijhy.png)
![=4000+5760+3960\\=13720](https://img.qammunity.org/2021/formulas/mathematics/college/xh4qsf3n6k9ujjtxdqvh52rkgiys4belpz.png)
Thus, the monthly cost of producing 24 standard model and 12 competition model surfboard per month is $13,720.
(2)
Compute the value of C (70, 7) as follows:
![C(x,\ y)=4000+240x+330y](https://img.qammunity.org/2021/formulas/mathematics/college/jq8jw0usj4wcr4vdsc0gftxbusohbhy20y.png)
![C(70,\ 7)=4000+(240 \cdot70)+ (330\cdot7)](https://img.qammunity.org/2021/formulas/mathematics/college/ldxrrb3z9kmroluv4ks6joohocpnnfw63w.png)
![=4000+16800+2310\\=23110](https://img.qammunity.org/2021/formulas/mathematics/college/xod1f1ekfqfqplk1psknfcdznhqn2d390v.png)
Thus, the monthly cost of producing 70 standard model and 7 competition model surfboard per month is $23,110.
(3)
Compute the value of C (30, 30) as follows:
![C(x,\ y)=4000+240x+330y](https://img.qammunity.org/2021/formulas/mathematics/college/jq8jw0usj4wcr4vdsc0gftxbusohbhy20y.png)
![C(30,\ 30)=4000+(240 \cdot30)+ (330\cdot30)](https://img.qammunity.org/2021/formulas/mathematics/college/u62szae9jptoirkvgmg62yhj4gvcregc1g.png)
![=4000+7200+9900\\=21100](https://img.qammunity.org/2021/formulas/mathematics/college/d4svf0otzmvj9ds1hv85htnafjo5l6b7ub.png)
Thus, the monthly cost of producing 30 standard model and 30 competition model surfboard per month is $21,100.