Math Joke:
2,000 mockingbirds = 2 kilomockingbirds
Lower Elementary
Question: Korey’s mom is planning a birthday party for him on April 20th. If today is Thursday, March 29th, on what day of the week will Korey’s party be?
Answer: Friday
Solution: In three more days it will be April 1st, which is a Sunday. Since the days of the week repeat every 7 days, the next three Sundays are April 8th, April 15th, and April 22nd. To find the day of the week for Korey’s birthday, move backwards two days from Sunday, April 22nd to Friday, April 20th.
Upper Elementary
Question: Last year, Jenny’s height was 5 feet 6.5 inches. This year, her height is 70 inches. How much did she grow?
Answer: 3.5 inches
Solution: First, because of the Law of Sameness, we need to convert 5 feet 6.5 inches into inches so that everything has the same name. There are 12 inches in a foot, so she was 66.5 inches last year (5 × 12 = 60 + 6.5 = 66.5 inches). Then we find how far it is from 66.5 inches up to 70 inches. It takes 0.5 inches to go from 66.5 inches to 67 inches and 3 inches to go from 67 inches to 70 inches, so it is 3.5 inches from 66.5 inches to 70 inches.
Middle School
Question: A dance team of 50 people is 48% girls. Of the girls, one sixth of them are wearing a red costume in the upcoming dance performance. How many girls are wearing red in the next set?
Answer: 4 Girls
Solution: First, find the number of girls that are on the team by finding 48% of 50. Then find 1/6 of that number to know the number of girls wearing a red costume.
Algebraic Method:
To find 48% of 50, change 48% to a decimal, 0.48. Then multiply by 50.
50 × 0.48 = 24
That means there are 24 girls on the team. Then, find 1/6 of 24 by multiplying 24 by 1/6.
24 × 1/6 = 4
So there are 4 girls wearing a red costume.
Number Sense Method:
Since Percent is For Each 100, to find 48% of 50 we see that 50 is half of 100 so that 48% of 50 will be half of 48.
Half of 48 = half of 40 + half of 8 = 20 + 4 = 24.
A sixth of 24 is 4, because dividing 24 into 6 equal pieces gives us 4 in each piece. So there are 4 girls wearing red in the next dance set.
Algebra and Up
Question: Jordan received the following scores on his chemistry tests this year so far: 91, 88, 93, 77, 79, 92, 88, and 84. He calculated that to get an A in the class, his test score average must be at least an 87. The only test left is the final exam, which is worth two test scores. What is the minimum that Jordan can score on the final exam to get an A in chemistry?
Answer: 89
Solution: The total of his current 8 test scores is 692 points. Let x be the final exam score. Since it is worth 2 test scores, we need to add 2x to his total (as if he is taking two tests and getting the same score on both). Now we have a “total” of 10 tests (since the final exam counts as 2 tests that receive the same score), and we want the average to be at least 87. So the equation we have is:
(692 + 2x) ÷ 10 = 87
692 + 2x = 870
2x = 178
x = 89
Jordan needs to score an 89 on the final exam if he wants an A in chemistry.
