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IM: 8.4.1: Number Puzzles (Lesson)

By Newsela Staff
Last updated 2 months ago
5 Questions
1.1: Notice and Wonder: A Number Line
1.

What do you notice? What do you wonder?

1.2: Telling Temperatures
Solve each puzzle. Show your thinking. Organize it so it can be followed by others.
2.

The temperature was very cold. Then the temperature doubled. Then the temperature dropped by 10 degrees. Then the temperature increased by 40 degrees. The temperature is now 16 degrees. What was the starting temperature?

3.

Lin ran twice as far as Diego. Diego ran 300 m farther than Jada. Jada ran 1/3 the distance that Noah ran. Noah ran 1200 m. How far did Lin run?

1.3: Making a Puzzle
Write another number puzzle with at least three steps on a piece of paper. On a different piece of paper, write a solution to your puzzle.

Trade puzzles with your partner and solve theirs. Make sure to show your thinking.

With your partner, compare your solutions to each puzzle. Did they solve them the same way you did? Be prepared to share with the class which solution strategy you like best.
Are you ready for more?

Here is a number puzzle that uses math. Some might call it a magic trick!

  1. Think of a number.
  2. Double the number.
  3. Add 9.
  4. Subtract 3.
  5. Divide by 2.
  6. Subtract the number you started with.
  7. The answer should be 3.
4.

Why does this always work?

5.

Can you think of a different number puzzle that uses math (like this one) that will always result in 5?