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Warm Up. Solve:. 4. 3. 6. Solve for m:. + -. Math 8H. Problem Solving Day 4 Mixture & Work Rate Problems. Algebra 1 Glencoe McGraw-Hill JoAnn Evans. Mixture Problems. These problems are just like COIN/VALUE/TICKET problems that we have already solved.
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Warm Up Solve: 4 3 6 Solve for m: +-
Math 8H Problem Solving Day 4 Mixture & Work Rate Problems Algebra 1 Glencoe McGraw-Hill JoAnn Evans
Mixture Problems These problems are just like COIN/VALUE/TICKET problems that we have already solved. You have value of items (money times #)
A 2-pound box of rice that is a mixture of white rice and wild rice sells for $1.80 per lb. White rice by itself sells for $0.75 per lb. and wild rice alone sells for $2.25 per lb. How much of each type of rice was used to make the mixture? Let x = pounds of wild rice Let 2 – x = pounds of white rice Remember, the entire box is 2 pounds. If the wild rice (x) is removed from the box, what is left? Entire box – wild rice 2 - x white rice
Val. of wild rice + Val. of white rice = Val. of Mixture + = 2.25 (2 – x) x 1.80 (2) 0.75 225x + 150 – 75x = 360 Remember, x was the amount of wild rice. 2-x is the amount of white rice. 150x + 150 = 360 150x = 210
Candy worth $1.05 per lb. was mixed with candy worth $1.35 per lb. to produce a mixture worth $1.17 per lb. How many pounds of each kind of candy were used to make 30 lbs of the mixture? Let x = amt. of $1.35 candy in mix Let 30 – x = amt. of $1.05 candy in mix
Value of $1.35 candy Value of $1.05 candy Value of mixture = + · · · = + (30 – x) x 135 105 117 30 135x + 3150 – 105x = 3510 30x + 3150 = 3510 30x = 360 x = 12 Solution: The mix will contain 18 lbs. of $1.05 candy and 12 lbs. of $1.35 candy.
“Work Rate” Problems Work rate problems are similar to the problems we did using the formula rate time = distance Instead now it’s: work rate time = part of work done
Work rate is the reciprocal of the time needed to complete the whole job. For example, if Andrew can complete a job in three hours………… he could complete of the job in an hour. His work rate is of the job per hour. work rate • time = part of work done
Erin owns a florist shop. It takes her 3 hours to arrange the flowers needed for a wedding. Her new assistant Niki can do the same job in 5 hours. How long will it take the two women to complete the job together? Let x = hours What is Erin’s work rate? What is Niki’s work rate?
The women will work together for x hours. What part of the job will each complete in x hours? Erin’s part + Niki’s part = 1 job
Charlotte and Corey share a car. Charlotte can wash and wax the car in two hours, but it takes Corey 3 hours to complete the same job. How long will it take them to wash and wax the car if they’re working together? Let x = hours Charlotte’s work rate: of the job per hour. Corey’s work rate: of the job per hour.
They will work together on the car for x hours. What part of the job could each complete alone in x hours? Charlotte’s part + Corey’s part = 1 job