Toy Train Cars: Turn-Around Facts and Grouping
0 / 11Toy Train Cars: Turn-Around Facts and Grouping
Change the order or the grouping to add an easier way.
Flip the Train
You can add numbers in any order. The sum stays the same.
1.
Eli's train has a car with 3 bears and a car with 8 bears. Then he turns the train around, so the car with 8 bears comes first.
3 + 8 =
8 + 3 =
2.
Two toy trains start at 0 on the track. Train A moves 4 spaces, then 9 more spaces. Train B moves 9 spaces, then 4 more spaces.
Train A stops at . Train B stops at .
3.
Max wants to find 2 + 9 by counting on. He wants to count on as few times as he can. What should he do?
4.
Write the turn-around fact for 9 + 6 = 15.
+ = 15
Hook Two Cars First
Add two numbers first to make a ten or a double. Then add the last number.
5.
A train has 3 cars. They carry 2 ducks, 6 ducks, and 4 ducks. Add 6 + 4 first.
2 + 6 + 4 = 2 + =
6.
Another train carries 4 sheep, 7 sheep, and 4 sheep. Add the double 4 + 4 first.
4 + 4 =
8 + 7 =
7.
Fill in the missing number so both sides have the same sum.
9 + 4 + 6 = 9 +
5 + 8 + 2 = 8 +
8.
Each train has three cars. Make a ten first. Match each train to its easier problem.
Same Sum Check
Use order and grouping to decide.
9.
Is each number sentence true or false? Sort them.
10.
Rina's train has cars with 6 toys, 7 toys, and 4 toys. Which train has the same number of toys as Rina's train?
11.
Nadia says 7 + 6 + 3 is the same as 10 + 6. Is she right? Find the sum and tell how you know.