Lower Elementary:
Question: Tony had $80. He spent $25 on dinner. His mom then gave him $40. How much money does Tony have now?
Answer: $95
Solution: Tony started with $80. He spent $25. $80 – $25 = $55. His mom then gave him $40. $55 + $40 = $95. Tony now has $95.
Upper Elementary:
Question: I am a three-digit number. I am divisible by 9. The tens digit is twice as large as the hundreds digit. The ones digit is the second smallest prime number. What is the number?
Answer: 243
Solution: The second smallest prime number is 3, so the ones digit is 3. The tens digit is twice as large as the hundreds digit. So, our hundreds digit cannot be greater than or equal to 5 since those numbers doubled are two-digit numbers. That means our possible numbers are 123, 243, 363, and 483. Of these choices, only 243 is divisible by 9 since 2 + 4 + 3 = 9 and 9 is divisible by 9.
Middle School:
Question: A grade point average is calculated using points. An A is worth 4 points, a B is worth 3 points, a C is worth 2 points, a D is worth 1 point, and an F is worth 0 points. If your grades for your classes are A, C, B, B, A, and A, what is your grade point average?
Answer: 3.33
Solution: First we will turn the letter grades into points using the number scale. An A is 4 points, a B is 3 points, and a C is 2 points. So the points for the classes are 4, 2, 3, 3, 4, and 4. Now we find the average of these numbers. 4 + 2 + 3 + 3 + 4 + 4 = 20. 20 ÷ 6 = 3 1/3 = 3.33. So your grade point average is a 3.33.
Algebra and Up:
Question: In a standard deck of 52 cards, what is the probability of drawing an Ace, keeping the card, and then drawing a face card?
Answer: 4/221
Solution: The number of Aces in a deck is 4, so the probability of drawing an Ace is 4/52. There are 12 face cards in the deck, and since we kept the first card, there are a total of 51 cards. So the probability of drawing a face card is 12/51. To find the total probability, we multiply both fractions. 4/52 • 12/51 = 1/13 • 4/17 = 4/221.
