A2 June 2025 Q5
5. Anvi makes boats during the winter months. She can make up to five boats each month.
If she builds more than three boats in any one month, she must hire an assistant at a cost of £400 for that month.
In any month in which boats are made, the overhead costs are £60 for each boat made that month.
A maximum of three boats can be held in storage at the end of each month, at a cost of £70 per boat per month.
Boats must be delivered at the end of each month.
The order schedule for boats is
| Month | November | December | January | February | March |
|---|---|---|---|---|---|
| Number ordered | 2 | 5 | 6 | 4 | 3 |
There are no boats in storage at the beginning of November.
Anvi plans to have no boats left in storage after the end of the March delivery.
[The table in the answer book begins as follows.]
| Stage | State | Action | Destination | Value |
|---|---|---|---|---|
| March | 3 | 0 | 0 | 210 = 210* |
| 2 | 1 | 0 | 140 + 60 = 200* | |
| 1 | 2 | 0 | 70 + 120 = 190* | |
| 0 | 3 | 0 | 180 = 180* |
The assistant asks to work in November, and Anvi agrees.
| Scheme | Marks | AO | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M1 A1 A1 A1 | 3.1a 1.1b 1.1b 1.1b | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| M1 A1ft A1 | 3.1a 1.1b 1.1b | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| M1 A1ft | 1.1b 1.1b | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| A1 | 1.1b | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| B1 | 2.2a | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Minimum cost: (£) 2540 | B1 | 2.2a | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| (12) |
Notes
All M marks – must bring earlier optimal results into calculations. Ignore extra rows. Must have right ‘ingredients’ (storage costs, overhead costs and workers) at least once per stage. Penalise lack of * only once per question. Additional rows which are not rejected are penalised by the loss of the final A mark in each stage
M1: Second stage completed. At least 9 rows, something in each cell. Condone extra rows
A1: Any one state correct
A1: All four states complete (13 rows) with any two states correct
A1: CAO for second stage no extra rows
M1: Third stage completed. 6 rows, something in each cell. Condone extra rows
A1ft: Any one state correct – ft their optimal values
A1: CAO for third stage no extra rows
M1: Fourth stage completed. 6 rows, something in each cell. Condone extra rows
A1ft: Correct fourth stage – ft their optimal values
A1: CSO all stages
B1: Correct allocation (dependent on all previous M marks)
B1: Correct minimum cost (dependent on all previous M marks)
Special Cases Maximises see below Max 7/12 in (a) If Minimax or Maximin seen send to review
SC Maximises Max M1 A1 A1 A0 M1 A1 A0 M1 A1 A0 B0 B0 (Max 7/12 in (a))
| Stage | State | Action | Dest | Value |
|---|---|---|---|---|
| March (3) | 3 | 0 | 0 | 210 = 210* |
| 2 | 1 | 0 | 140 + 60 = 200* | |
| 1 | 2 | 0 | 70 + 120 = 190* | |
| 0 | 3 | 0 | 180 = 180* | |
| Feb (4) | 3 | 1 | 0 | 210 + 60 + 180 = 450 |
| 2 | 1 | 210 + 120 + 190 = 520 | ||
| 3 | 2 | 210 + 180 + 200 = 590 | ||
| 4 | 3 | 210 + 240 + 400 + 210 = 1060* | ||
| 2 | 2 | 0 | 140 + 120 + 180 = 440 | |
| 3 | 1 | 140 + 180 + 190 = 510 | ||
| 4 | 2 | 140 + 240 + 400 + 200 = 980 | ||
| 5 | 3 | 140 + 300 + 400 + 210 = 1050* | ||
| 1 | 3 | 0 | 70 + 180 + 180 = 430 | |
| 4 | 1 | 70 + 240 + 400 + 190 = 900 | ||
| 5 | 2 | 70 + 300 + 400 + 200 = 970* | ||
| 0 | 4 | 0 | 240 + 400 + 180 = 820 | |
| 5 | 1 | 300 + 400 + 190 = 890* | ||
| Jan (6) | 3 | 3 | 0 | 210 + 180 + 890 = 1280 |
| 4 | 1 | 210 + 240 + 400 + 970 = 1820 | ||
| 5 | 2 | 210 + 300 + 400 + 1050 = 1960* | ||
| 2 | 4 | 0 | 140 + 240 + 400 + 890 = 1670 | |
| 5 | 1 | 140 + 300 + 400 + 970 = 1810* | ||
| 1 | 5 | 0 | 70 + 300 + 400 + 890 = 1660* | |
| Dec (5) | 3 | 3 | 1 | 210 + 180 + 1660 = 2050 |
| 4 | 2 | 210 + 240 + 400 + 1810 = 2660 | ||
| 5 | 3 | 210 + 300 + 400 + 1960 = 2870* | ||
| 2 | 4 | 1 | 140 + 240 + 400 + 1660 = 2440 | |
| 5 | 2 | 140 + 300 + 400 + 1810 = 2650* | ||
| 1 | 5 | 1 | 70 + 300 + 400 + 1660 = 2430* | |
| Nov (2) | 0 | 3 | 1 | 180 + 2430 = 2610 |
| 4 | 2 | 240 + 400 + 2650 = 3290 | ||
| 5 | 3 | 300 + 400 + 2870 = 3570* |
| Scheme | Marks | AO |
|---|---|---|
| Additional cost is (£) 140 | B1 | 2.2a |
| (1) | ||
| (13 marks) |
Notes
B1: CAO (dependent on all M marks in (a))