Mrs. Kim had 20 pencils. She gave 3 to each of her 4 students. How many pencils does she have left? — 8.She gave 3 × 4 = 12 pencils. 20 − 12 = 8 left.
Which equation matches: "Emma had 10 cookies, ate 3, and got 5 more"? — 10 − 3 + 5 = 12.Ate 3 = subtract; got 5 more = add. 10 − 3 + 5 = 12.
There are 7 children on a bus. 4 more get on at a stop. Then 2 get off. How many are on the bus now? — 9.7 + 4 = 11; 11 − 2 = 9 children.
A pond has 5 frogs. 3 more frogs jump in. Then 1 jumps out. How many frogs are in the pond? — 7.5 + 3 = 8; 8 − 1 = 7 frogs.
A pet store has 8 cats and 7 dogs. 3 cats are sold. How many pets are left? — 12.8 − 3 = 5 cats remain; 5 + 7 = 12 pets.
There were 11 books on a shelf. A librarian added 4 and then removed 6. How many books are on the shelf? — 9.11 + 4 = 15; 15 − 6 = 9 books.
A train has 6 cars. At the station, 3 more cars are added and 2 are removed. How many cars are on the train now? — 7.6 + 3 = 9; 9 − 2 = 7 cars.
Find the missing number: __ + 5 = 5 + 9 — 9.By the commutative property, __ = 9. Both sides equal 14.
Which is NOT a correct use of the equal sign? — 3 = 4 + 7.3 ≠ 4 + 7 (which equals 11). The others are all correct.
What number goes in the box? 14 = □ + 6 — 8.14 − 6 = 8. So □ = 8, making 8 + 6 = 14.
A scale is balanced with 7 on the left. The right side has 4 + ?. What is ?? — 3.For balance: 7 = 4 + 3. So ? = 3.
Which is the correct check for __ + 7 = 15 → __ = 8? — 8 + 7 = 15 ✓.Plug 8 back in: 8 + 7 = 15. It checks out!
__ + __ = 10 using two equal numbers. What are they? — 5 and 5.5 + 5 = 10 — both equal numbers are 5!
Max had some stickers, gave away 5, and had 9 left. How many did he start with? — 14.9 + 5 = 14. He started with 14 stickers.
3 + __ = __ + 3 = 11. What is the missing number? — 8.3 + 8 = 11. Both blanks are 8 — this also shows the commutative property!
Bella knows 12 − 7 = 5. What other THREE facts does she know? — 12−5=7; 7+5=12; 5+7=12.Family 5, 7, 12: 12−5=7; 7+5=12; 5+7=12. All four facts!
Which set of equations is a complete fact family for 8, 5, 13? — 8+5=13; 5+8=13; 13−5=8; 13−8=5.A complete fact family has all four facts!
Write a fact family with 4, 8, 12. Which equation is NOT correct? — 8 − 4 = 12.8 − 4 = 4, not 12! The correct subtraction facts are 12 − 4 = 8 and 12 − 8 = 4.
A box holds 14 crayons. After some are removed, 9 are left. Use the fact family to find how many were removed. — 5.14 − 9 = 5. The fact family 5, 9, 14 tells us 5 crayons were removed.
True or False: The family 3, 3, 6 has only 3 unique facts (not 4). — True.3+3=6; 6−3=3. When both addends are the same, there are fewer unique facts!