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3. Light roast coffee beans cost $7.00/1b, while dark roast costs $5.50/1b. How much of each type of coffee is needed to creat 4.50 pounds of a mixture that costs $6.75 per pound? 4. Light roast coffee beans cost $6.00/1b, while dark roast costs $4.50/1b. How much of each type of coffee is needed to create 3.50 pounds of a mixture that costs $5.00 per pound? 5. Company A charges a fixed S200 for painting services, along with a $20 hour labor for Company B charges a strict hourly rate of $45/hout. For what length of time would the cost of both company's services be the same? 6. The supply equation for a certain product is given by 209 - 40p - 800 The demand equation for the same product is given by 109 + 20p = 1200 Find the equilibrium point. 7. A person spends $300,000 on a total of 3 properties. The first property's value is the sum of the other two properties. The second property is twice the value of the third property. How much does each property cost? 8. A person spends S560,000 on a total of 3 properties. The first property's value is the sum of the other two properties. The second property is three times the value of the third property. How much does each property cost? 9.1 pound of cercal A contains 10g of potassium, 28 of calcium, and 4g of magnesium. 1 pound of cereal B contains 6g of potassium, Og of calcium, and 3g of magnesium 1 pound of cercal C contains 12g of potassium, 6g of calcium, and 2g of magnesium. How many pounds of each cereal is needed to have a mixture containing 988 of potassium, 28g of calcium, and 32g of magnesium? 10. 1 pound of cereal A contains 10g of potassium, 2g of calcium, and 4g of magnesium. 1 pound of cercal B contains og of potassium, Og of calcium, and 3g of magnesium. 1 pound or cereal C contains 12g of potassium, og of calcium, and 2g of magnesium. How many pounds of each cereal is needed to have a mixture containing S6g of potassium, 16g of calcium, and 18g of magnesium? 11. S24000 is invested in three different accounts, each paying 1%, 2%, and 3% interest, respectively. After 1 year, the simple interest cared from all three accounts amounts to $440. If the account paying 1% interest contains three times the amount in the account paying 2% interest, how much was invested in the three accounts