22270d
1) Since the sales have been modeled by this recursive formula, we need to make reference to the prior item in the sequence to find the next one:
a) P_1 and P_2
![\begin{gathered} P_n=P_(n-1)+12000 \\ P_1=27000+12000 \\ P_1=39000 \\ --- \\ P_2=39000+12000 \\ P_2=51000 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/1e42iqd1jwbtdlx42wrc70s1j9robfb6ku.png)
Note that whenever we have a recursive formula we'll need the prior item to get the subsequent one.
b) Explicit formula for P_N
When we have an explicit formula, we don't need the prior term. So let's find an explicit one:
![P_N=27000+12000N](https://img.qammunity.org/2023/formulas/mathematics/college/spmwhrqinw9hwslnomtgc9hk2enyqsey6z.png)
Note that the difference between P_2 and P_1 is 12,000.
c) Now, let's pick this explicit formula and find P_10:
![\begin{gathered} P_(10)=27000+12000\cdot10 \\ P_(10)=147,000 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/o4tuxsz415gkcdo7wz0srwyxh6zf26vfvv.png)
d) Let's use the explicit formula to find when, in years the store is going to exceed 97000
97000=27000+12