🧮 Part 1: Mental Addition Practice

267 + 40 = ______

First I add _____ to reach 300, then I add _____ more to get _____

384 + 50 = ______

First I add _____ to reach 400, then I add _____ more to get _____

456 + 70 = ______

First I add _____ to reach 500, then I add _____ more to get _____

a) 278 + 30 = ______

b) 195 + 60 = ______

c) 347 + 80 = ______

d) 589 + 40 = ______

🎯 Part 2: True or False

a) Adding 30 always changes the hundreds digit.

True / False

b) When adding tens, the ones digit never changes.

True / False

c) 699 + 20 = 719

True / False

d) To add 50 to 367, I can add 30 then add 20.

True / False

💭 Part 3: Problem Solving

Answer: _______ marbles