Toy Factory Number Machines
0 / 13Toy Factory Number Machines
Find the missing number in each equation.
Number machines
Each machine changes every number that goes in. Write the missing numbers.
1.
Machine A adds 6 to every number.
9 + 6 =
+ 6 = 13
+ 6 = 10
2.
Machine B takes away 4 from every number.
12 − 4 =
− 4 = 11
− 4 = 5
3.
A mystery machine changes 8 into 13. It changes 10 into 15. What does the machine do?
8 + ? = 13
10 + ? = 15
8 + ? = 13
10 + ? = 15
4.
Machine C takes away the same number every time. It changes 17 into 9.
17 − = 9
Machine C changes 14 into .
Factory equations
Find the number that makes each equation true.
5.
+ 8 = 12
15 = + 7
13 − = 4
− 5 = 7
6 = 16 −
= 7 + 7
6.
A box holds 16 toy cars. 7 cars are red. The rest are blue. Which equation can you use to find the number of blue cars?
7.
Circle every equation where ? is 8.
8.
Both sides of the equal sign must make the same number. Find the missing number.
8 + 5 = + 6
Factory stories
Write the missing number in each equation to answer the question.
9.
The factory makes 9 teddy bears in the morning. It makes more bears in the afternoon. It makes 15 bears in all. How many bears does it make in the afternoon?
9 + = 15
10.
Some yo-yos are on a shelf. A worker packs 6 yo-yos in a box. Now 7 yo-yos are left on the shelf. How many yo-yos were on the shelf at first?
− 6 = 7
11.
A robot has 18 bolts. It uses some bolts to build a toy truck. It has 10 bolts left. How many bolts did it use?
18 − = 10
12.
Which equation has the same missing number as 5 + ? = 12?
13.
The factory needs 20 toy boats. It has made 12 boats. How many more boats does it need to make? Write an equation with a ? for the missing number. Then solve it.