B1.3 Round whole numbers to the nearest ten or hundred, in various contexts.
Activity 1: Who is Closest to 1000?
Materials
- 3 9-sided dice
Directions
Explain the rules of the dice game "Who is Closest to 1000?.
- Roll the 3 dice.
- Place the dice to form a number.
- The person with the number closest to 1000 wins a point.
- You can choose to round the number formed with the 3 dice.
- If the players have the same number, each player gets one point.
- Explain your choice of number using the benchmark numbers on a number line.
- The first player to reach 5 points wins the game.
Source: inspired by En avant, les maths!, 3e année, ML, Nombres, p. 3-4.
Activity 2: Rounding Numbers According to Context
Benevolence School held a fundraiser to replenish the community's food bank. The students raised $885. The school administration would like to make the big announcement at the next assembly in the gym.
Ask students questions such as:
- In this situation, should the number be rounded? Why?
- Should the number be rounded up or down? Explain your reasoning.
- In your opinion, should the adminstrators round up the amount of money to the nearest ten or hundred during the big announcement? Justify your answer.
- What do you notice when you round the number to the nearest ten? to the nearest hundred?