Presentation on theme: "Number Lines Friend or Foe?!? 3548279991,236123241."— Presentation transcript:
Number Lines Friend or Foe?!? ,
How do number lines help us? Rounding Finding a midpoint Ordering numbers Adding numbers Subtracting numbers Skip counting (multiplication) Math
Rounding Round the number to the nearest hundreds place: 765 Old School: Mathematical Thinker: The six is higher than five, so you have to round up. I know that 765 is in between 700 and is greater than the midway point of 750, so it must round up to 800. I also know that on a number line, 765 is much closer to 800 than 700.
Ordering Numbers Put the numbers in order from least to greatest: Old School Mathematical Thinker: Look at the largest place value, find the smallest number, it goes first. If the numbers are the same, go to the next place value… On a number line, I know that fifty comes right before 55, so I will put it there. Both 62 and 67 are in the 60s, but 62 is closer to 60 while 67 is closer to 70.
Adding and Subtracting Solve Old School Mathematical Thinker is 12, so I put down the 2 and carry the 1. I know that if I add 200 to 345, I will jump to 545. Then if I add another 5, I am at 550…
What happens when students don’t think about numbers
Your turn! No groaning! = 12, ,236 = 4,123 – 956 =