AI Tutor
Imagine you have 14 crunchy pretzels, and your friend asks for 6. How can you share them quickly in your head without counting backwards one by one?

Landing on Ten

The number 14 is made of one full ten and 4 extra ones. Ten is a friendly landing spot because subtracting from 10 is easy.
How can we use our friendly 10 to solve 14βˆ’614 - 6 in two quick jumps?

Break Apart and Subtract

First, take away the 4 extra ones to get straight to 10. Since 14βˆ’4=1014 - 4 = 10, we have reached our safe base.
We needed to subtract 6 in all. Since we already took away 4, we split 6 into 4 and 2, leaving 2 more to subtract.
Now just subtract the remaining 2 from 10: 10βˆ’2=810 - 2 = 8. So, 14βˆ’6=814 - 6 = 8!
What happens if we try a different problem like 13βˆ’513 - 5?

Let's Try 13 - 5

Start at 13. To land on 10, look at the ones digit: we need to subtract 3 first.