Lower Elementary
Question: Gina bought 72 blueberries to make a mini-pie. She used half of them to make the mini-pie. She then ate an additional 8 for a snack. How many blueberries does Gina have left after her snack?
Answer: 28 blueberries
Solution: Half of 72 is 36. Gina used 36 blueberries to make the mini-pie. Subtract 8 for the amount she ate for her snack. 36 – 8 = 28. She has 28 blueberries left.
Upper Elementary
Question: Rob, Jordan, and Isabella ate a total of 18 mini-pies. Rob ate 1/6 of the mini-pies, and Jordan ate 1/3 of the mini-pies. How many mini-pies did Isabelle eat?
Answer: 9 mini-pies
Solution: Rob ate 1/6 of the pies and Jordan ate 1/3 of the pies, which adds to 1/2(1/6 + 2/6 = 3/6 = 1/2). That means that Isabelle ate half of the mini-pies. Half of 18 is 9, so Isabelle ate 9 mini-pies.
Middle School
Question: Bonnie is baking a pie. The recipe for the filling calls for 3 cups of diced apples, 3/4 cups of sugar, 1/2 a cup of flour, and 1/8 a cup of other ingredients. How many total cups is the filling?
Answer: 4 3/8 cups
Solution: The Law of Sameness says to add things, they must have the same name. For fractions, this means the same denominator. The smallest number that 4, 2, and 8 can go into is 8; This means we can rename the fractions as eighths.
3/4 = 6/8
1/2 = 4/8
1/8 = 1/8
6/8 + 4/8 + 1/8 = 11/8 = 1 3/8
Add the 3 cups of apples, and the total amount of the mixture comes to 4 3/8 cups.
Algebra and Up
Question: A circle is inscribed in a square that has a length of 20 cm. What is the area of the circle? (leave your answer in terms of π).
Answer: 100π cm
Solution: Since the circle is inscribed in the square, that means the diameter is the same as the length of the square. The area of a circle is π*r^2. The diameter is 20, so the radius is 10. The area is:
A = pi * (10)^2 = 100π cm
