Presentation on theme: "Motion, Money, and Mixture Problems"— Presentation transcript:
1Motion, Money, and Mixture Problems Section 3.4Motion, Money, and Mixture Problems
2Solving Motion Problems Formula: Distance = rate x time(D = rt)Make a table:ITEMRATE xTIME =DISTANCEItem1Distance 1Item 2Distance 2
3Fill in the information you know, and set up the variable. Multiply rate by time to get each distance.To write the equation, READ the problem carefully. It could be:Distance 1 – Distance 2 = ___Distance 1 + Distance 2 = ___Distance 1 = Distance 2
4Examples, from p 2118) 2 trains in NYC start at the same station going in the same direction on sets of parallel tracks. The local train stops often and averages 18.4 mph. The express train stops less frequently and averages 30.2 mph. In how many hours will the 2 trains by 5.9 miles apart?
516) To get to the top of Whistler Mountain, people must use 2 different ski lifts. The first lift travels 4 mps for 0.2 hours. The 2nd lift travels for 0.3 hours to reach the top of the mountain. If the total distance traveled is 1.2 miles, find the average speed of the 2nd lift.
612) Barb and Sandy are at opposite ends of a shopping mall 4780 12) Barb and Sandy are at opposite ends of a shopping mall feet apart walking towards each other. If Barb walks 1.5 ft per second and Sandy walks 2.2 ft per second, how long will it be before they meet?
7Solving Money problems Formula: Interest = Principal x rate x time (in years)(I = PRT)Make a table:AccountPrincipal xRate xTime =InterestAccount 1Interest 1Account 2Interest 2
8Examples, p 21334) Jerry invested $7000, part at 8% simple interest and the rest at 5% simple interest for a period of 1 year. If he received a total annual interest of $476 from both investments, how much did he invest at each rate?
938) Sharon invested $20,000, part at 5% and part at 7% simple interest for a period of 1 year. How much was invested in each account if the interest earned in the 7% account was $440 greater than the interest earned in the 5% account?
10Mixture Problems Quantity x Price (or %) = Amount Set up another table!Amount 1 + Amount 2 = Amount MixtureQuantity xPrice per unit or strength % =AmountItem 1Amount of 1Item 2Amount of 2MixtureAmount of mix
1250) At Agway Gardens, bird food is sold in bulk 50) At Agway Gardens, bird food is sold in bulk. In one barrel are sunflower seeds that sell for $1.80 per lb. In a second barrel is cracked corn that sells for $1.40 per lb. If a mixture is made by taking 2.5 lbs of sunflower seeds and 1 lb of cracked corn, what should the mixture per lb cost?
13From p 21454) Susan, a pharmacist, has a 60% solution of sodium iodite. She also has a 25% solution of the same drug. She gets a prescription calling for a 40% solution of the drug. How much of each solution should she mix to make 0.5 liter of the 40% solution?