Click here [1] for the Problem Extension Worksheet version of the Problems of the Week.
Click here [2] for an MS Word version of the Problems of the Week.
Click here [3] for the Canadian Problem Extension Worksheet version of the Problems of the Week.
Click here [4] for a Canadian MS Word version of the Problems of the Week.
[5]Lower Elementary:
Question: Anthony is baking cookies for his friends. He bakes 2 dozen cookies, but 5 of them crumble into pieces. If Anthony needs 18 cookies for his friends, then how many cookies does he have left over for himself?
Answer: 1 cookie
Solution: Since a dozen is 12, Anthony bakes 12 + 12 = 24 cookies. He has 24 – 5 = 19 to give to his friends after 5 of them crumble. Since he needs 18 cookies for his friends, he has 19 – 18 = 1 cookie leftover for himself.
[5]Upper Elementary:
Question: Betsy buys 6 cookies from the store. The cookies have 5, 9, 10, 6, 7, and 11 chocolate chips in them, respectively. What is the average number of chocolate chips per cookie?
(Hint: The average is the sum of all the values in a set, divided by the number of values in the set.)
Answer: 8 chocolate chips
Solution: To find an average, we add up all the values in a set and then divide by the number of values. So, since there are 5 + 9 + 10 + 6 + 7 + 11 = 48 chocolate chips among 6 cookies, that means that the average is 48 ÷ 6 = 8 chocolate chips per cookie.
[5]Middle School:
Question: Chris needs to preheat his oven to 345°F to bake a batch of chocolate chip cookies. The oven has an internal temperature of 70°F when it’s turned off. If it heats at an average rate of 22°F per minute from the moment Chris turns it on to the moment it reaches 345°F, then exactly how long will it take for the oven to reach the correct temperature?
Answer: 12 minutes and 30 seconds
Solution: Since Chris needs the oven to heat up by 345°F – 70°F = 275°F. The average increase in temperature per minute is 22°F, so if we divide the amount the oven needs to heat up by the average increase in temperature per minute, we find that it takes 275°F ÷ 22°F per minute = 12 minutes and 30 seconds for the oven to preheat.
[5]Algebra and Up:
Question: Daria owns a small bakery whose projected total profit can be modeled with the function f(x) = 4,750x + 10,800. If x is a number of months measured from now and the output is a number of dollars, find the projected total profit for 2 years from now.
Answer: $124,800
Solution: There are 24 months in 2 years, so we find the output value of f(x) when x is 24. So, since f(24) = 4,750(24) + 10,800 = 124,800, the bakery is projected to earn a total profit of $124,800 in the next 2 years.