Problems of the Week: January 20-24

Jan 21, 2020 | North Alpharetta

Each week, Mathnasium publishes math problems to be completed by students. We give students time to work on these during their sessions, as the problems are posted in the center. Below are the problems for the week of January 13-17: ask your students about the problem that best fits their math level! Can they solve it? (Solutions are attached below their respective problems)

 

Lower Elementary:
Question: Stacy has tickets to a concert that starts at 8:30 PM. If it’s currently 7:42 PM, then how much time does Stacy have to get to the concert before it starts?
Answer: 48 minutes
Solution: We can solve this problem by building up to 8:30. There are 18 minutes until 8:00 because 42 + 18 = 60 minutes, or an hour. There are 30 minutes from 8:00 until 8:30. So, Stacy has 18 + 30 = 48 minutes until the concert starts.

Upper Elementary:
Question: Maggie wants to buy a puzzle that costs $25. She has a 50% off coupon and $10. How much more money does Maggie need to get the puzzle?
Answer: $2.50
Solution: Half of $25 is $12.50. Maggie already has $10, so she needs $12.50 – $10 = $2.50 more.

Middle School:
Question: A red token is worth twice as much as an orange token. An orange token is worth 5 less a yellow token. A yellow token is worth 15 less than a green token. A green token is worth half as much as a blue token, and a blue token is worth B. How much is a yellow token worth in terms of B?
Answer: 0.5B – 15
Solution: If a blue token is worth B, then a green token is worth half of B, or 0.5B. A yellow token is worth 15 less, so that’s 0.5B – 15.

Algebra and Up:
Question: The formula for the temperature in Fahrenheit (F) in terms of the temperature in Celsius (C) is: F = 9C/5 + 32


What is the formula for the temperature in Celsius in terms of the temperature in Fahrenheit?
Answer: C = 5/9(F – 32)
Solution: First, we subtract 32 from both sides and get F – 32 = 9C ÷ 5. Next, we multiply each side by 5 and get 5(F – 32) = 9C. After that, we divide each side by 9 and get 5/9(F – 32) = C. Finally, we flip it around and get C = 5/9(F – 32).