Let's solve each problem step by step:

1. Michael's Price Discount

• Original price of the jeans: $80 \,€$
• Discount: $10 \,€$

We need to find the percentage discount:

$\text{Discount percentage} = \left(\frac{\text{Discount}}{\text{Original price}}\right) \times 100$ $\text{Discount percentage} = \left(\frac{10}{80}\right) \times 100 = 12.5\%$

So, the discount percentage is 12.5%.

2. Frau Klug's Watch Price

• Paid price: $48 \,€$
• Discount: $40\%$ off the original price.

Let the original price be $x$.

$x - 0.40x = 48$ $0.60x = 48$ $x = \frac{48}{0.60} = 80 \,€$

The original price of the watch is 80 €.

3. Herr Maier's Net Income

• Gross income: $2400 \,€$
• Tax rate: $35\%$

Net income can be calculated as:

$\text{Net income} = \text{Gross income} - (\text{Gross income} \times \text{Tax rate})$ $\text{Net income} = 2400 - (2400 \times 0.35) = 2400 - 840 = 1560 \,€$

Herr Maier's net income is 1560 €.

Would you like further details on any of these calculations?

Here are 5 follow-up questions:

1. How can we calculate the original price of an item if the discount percentage and the sale price are known?
2. What is the formula to calculate the percentage discount?
3. How do we calculate the amount of tax deducted from a given income?
4. What other methods could be used to find the original price if given a percentage discount?
5. How would the results change if the tax rate for Herr Maier was reduced to 25%?

Tip: When solving percentage problems, always set up the relationship between parts and whole values clearly to avoid mistakes.