1. **Problem Statement:**
A trader buys 50 kg of type q groundnuts at 130 per kg and 75 kg of type r groundnuts at 180 per kg, then mixes them.
2. **(a)(i) Find the cost price per kg of the mixture:**
- Total cost of type q = $50 \times 130 = 6500$
- Total cost of type r = $75 \times 180 = 13500$
- Total weight = $50 + 75 = 125$ kg
- Total cost = $6500 + 13500 = 20000$
- Cost price per kg of mixture = $\frac{20000}{125} = 160$
3. **(a)(ii) Calculate percentage profit when 80% sold at 170 and 20% at 180:**
- Total mixture weight = 125 kg
- Weight sold at 170 = $0.8 \times 125 = 100$ kg
- Weight sold at 180 = $0.2 \times 125 = 25$ kg
- Revenue from 170/kg = $100 \times 170 = 17000$
- Revenue from 180/kg = $25 \times 180 = 4500$
- Total revenue = $17000 + 4500 = 21500$
- Cost price = $20000$
- Profit = $21500 - 20000 = 1500$
- Percentage profit = $\frac{1500}{20000} \times 100 = 7.5\%$
4. **(b) Find the ratio of mixing for 25% profit when selling at 200 per kg:**
- Let the ratio of type q to type r be $x : y$
- Cost price per kg of mixture = $C = \frac{130x + 180y}{x + y}$
- Selling price per kg = 200
- Profit = 25%, so selling price = $1.25 \times C$
- Therefore, $200 = 1.25 \times C \Rightarrow C = \frac{200}{1.25} = 160$
- Set up equation: $\frac{130x + 180y}{x + y} = 160$
- Multiply both sides by $(x + y)$: $130x + 180y = 160x + 160y$
- Rearrange: $180y - 160y = 160x - 130x \Rightarrow 20y = 30x$
- Simplify ratio: $\frac{x}{y} = \frac{20}{30} = \frac{2}{3}$
**Final answers:**
- (a)(i) Cost price per kg of mixture = 160
- (a)(ii) Percentage profit = 7.5%
- (b) Ratio of mixing type q to type r = 2 : 3
Groundnuts Mixture
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