35 minutes · Pair work · Calculator. Both portfolios start at SEK 10,000. Companies and changes are invented. Cash stays unchanged. No deposits, withdrawals, fees, taxes, dividends or currency effects are included.
On screen, the table can scroll sideways.
| Holding | Group One | Group Two |
|---|---|---|
| Company A | SEK 6,000 | SEK 2,000 |
| Company B | SEK 2,000 | SEK 6,000 |
| Cash | SEK 2,000 | SEK 2,000 |
| Total | SEK 10,000 | SEK 10,000 |
Scenario 1: A −10%, B +20%
Calculate A, B and cash, then add the total. Calculate the change from SEK 10,000 and A’s new weight within the new total.
On screen, the table can scroll sideways.
| Measure | Group One | Group Two |
|---|---|---|
| Ending A | SEK 5,400 | SEK 1,800 |
| Ending B | SEK 2,400 | SEK 7,200 |
| Cash | SEK 2,000 | SEK 2,000 |
| Total | SEK 9,800 | SEK 11,000 |
| Change (%) | −2 % | +10 % |
| A’s new weight (%) | 55.1 % | 16.4 % |
Scenario 2: A +20%, B −10%
Calculate A, B and cash, then add the total. Calculate the change from SEK 10,000 and A’s new weight within the new total. Restart from the starting table; this is an alternative to scenario 1.
On screen, the table can scroll sideways.
| Measure | Group One | Group Two |
|---|---|---|
| Ending A | SEK 7,200 | SEK 2,400 |
| Ending B | SEK 1,800 | SEK 5,400 |
| Cash | SEK 2,000 | SEK 2,000 |
| Total | SEK 11,000 | SEK 9,800 |
| Change (%) | +10 % | −2 % |
| A’s new weight (%) | 65.5 % | 24.5 % |
Exit task: both companies fall
Restart again. A and B both fall by 10%. What are the total and percentage change for each group? Explain why the outcome is equal.
Both finish at SEK 9,200: −8%. Each has SEK 8,000 in stocks, losing SEK 800, and SEK 2,000 in unchanged cash. Assess whether students calculate the parts first, use the new total for weights and distinguish an assumed outcome from a general investment rule.