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Applications of Equations Lesson 2.3 What are we doing? Basically, everything we learned in the previous two lessons will be applied to real world situations or unique situations that will call upon our newly gained knowledge Example The average of two real numbers is 39.625, and one number is 1500 times the reciprocal of the other. Find the two numbers. Yet another example The width of a rectangle is three times its height. If it has an area of 60.75 square feet, what are its dimensions? Example Number 3 A storage locker in the shape of a rectangular prism with a square floor has a volume of 70,000 cubic inches. If the surface area of the four walls and the top is 10,000 square inches, what are the dimensions of the locker? I = PRT {Simple Interest} I Interest {fee paid for use of money} P Principal {amount put in} r rate {annual interest rate} t time {represented in years} Example A real estate investment yields a return of 10% per year and a certificate of deposit (CD) pays 6% interest per year. How much of $7500 should be put in the real estate investment and how much should be put in the CD to obtain a return of 7% on the entire $7500? Example…again? A pilot wants to make an 840 mile round trip form Cleveland to Peoria and back in 5 hours flying time. There will be a headwind of 30 mph going to Peoria, and it is estimated that there will be a 40-mph tailwind returning to Cleveland. At what constant engine speed should the plane be flown? All about the examples A car radiator contains 12 quarts of fluid, 20% of which is antifreeze. How much fluid should be drained and replaced with pure antifreeze so the resulting mixture is 50% antifreeze? Last One, I promise! A container in the shape of a rectangular prism with no top that has a volume of 650 cubic inches is to be constructed from a 28 x 20 inch piece of sheet metal by cutting squares of equal size from each corner and folding up the flaps. What size square should be cut from each corner?