Function Machines (Inputs and Outputs) Worksheet | 8th Grade PDF ... - Free Printable

Here are the solutions for the function machine problems.

Section A: Find the Outputs

*Apply the operation shown in the box to each input number.*

1. Add 5
* $2 + 5 = \mathbf{7}$
* $4 + 5 = \mathbf{9}$
* $5 + 5 = \mathbf{10}$
* $11 + 5 = \mathbf{16}$

2. Add 8
* $4 + 8 = \mathbf{12}$
* $12 + 8 = \mathbf{20}$
* $6 + 8 = \mathbf{14}$
* $5 + 8 = \mathbf{13}$

3. Add 15
* $1 + 15 = \mathbf{16}$
* $4 + 15 = \mathbf{19}$
* $3 + 15 = \mathbf{18}$
* $15 + 15 = \mathbf{30}$

4. Subtract 1
* $13 - 1 = \mathbf{12}$
* $4 - 1 = \mathbf{3}$
* $9 - 1 = \mathbf{8}$
* $23 - 1 = \mathbf{22}$

5. Subtract 8
* $20 - 8 = \mathbf{12}$
* $13 - 8 = \mathbf{5}$
* $36 - 8 = \mathbf{28}$
* $84 - 8 = \mathbf{76}$

6. Subtract 20
* $22 - 20 = \mathbf{2}$
* $156 - 20 = \mathbf{136}$
* $108 - 20 = \mathbf{88}$
* $53 - 20 = \mathbf{33}$

7. Multiply by 2
* $4 \times 2 = \mathbf{8}$
* $6 \times 2 = \mathbf{12}$
* $10 \times 2 = \mathbf{20}$
* $2 \times 2 = \mathbf{4}$

8. Multiply by 5
* $8 \times 5 = \mathbf{40}$
* $11 \times 5 = \mathbf{55}$
* $7 \times 5 = \mathbf{35}$
* $9 \times 5 = \mathbf{45}$

9. Divide by 2
* $8 \div 2 = \mathbf{4}$
* $40 \div 2 = \mathbf{20}$
* $100 \div 2 = \mathbf{50}$
* $24 \div 2 = \mathbf{12}$

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Section B: Complete Inputs and Outputs

*Use the opposite (inverse) operation if you have the Output and need the Input.*

1. Add 4
*(Inverse is Subtract 4)*
* Input: $1 \rightarrow$ Output: $1 + 4 = \mathbf{5}$
* Output: $12 \rightarrow$ Input: $12 - 4 = \mathbf{8}$
* Output: $29 \rightarrow$ Input: $29 - 4 = \mathbf{25}$
* Input: $46 \rightarrow$ Output: $46 + 4 = \mathbf{50}$

2. Add 7
*(Inverse is Subtract 7)*
* Output: $13 \rightarrow$ Input: $13 - 7 = \mathbf{6}$
* Input: $13 \rightarrow$ Output: $13 + 7 = \mathbf{20}$
* Output: $19 \rightarrow$ Input: $19 - 7 = \mathbf{12}$
* Input: $21 \rightarrow$ Output: $21 + 7 = \mathbf{28}$

3. Add 12
*(Inverse is Subtract 12)*
* Input: $6 \rightarrow$ Output: $6 + 12 = \mathbf{18}$
* Output: $30 \rightarrow$ Input: $30 - 12 = \mathbf{18}$
* Output: $74 \rightarrow$ Input: $74 - 12 = \mathbf{62}$
* Output: $98 \rightarrow$ Input: $98 - 12 = \mathbf{86}$

4. Subtract 1
*(Inverse is Add 1)*
* Output: $10 \rightarrow$ Input: $10 + 1 = \mathbf{11}$
* Output: $17 \rightarrow$ Input: $17 + 1 = \mathbf{18}$
* Input: $8 \rightarrow$ Output: $8 - 1 = \mathbf{7}$
* Output: $99 \rightarrow$ Input: $99 + 1 = \mathbf{100}$

5. Subtract 3
*(Inverse is Add 3)*
* Input: $7 \rightarrow$ Output: $7 - 3 = \mathbf{4}$
* Output: $1 \rightarrow$ Input: $1 + 3 = \mathbf{4}$
* Output: $3 \rightarrow$ Input: $3 + 3 = \mathbf{6}$
* Input: $351 \rightarrow$ Output: $351 - 3 = \mathbf{348}$

6. Subtract 5
*(Inverse is Add 5)*
* Output: $5 \rightarrow$ Input: $5 + 5 = \mathbf{10}$
* Output: $13 \rightarrow$ Input: $13 + 5 = \mathbf{18}$
* Output: $24 \rightarrow$ Input: $24 + 5 = \mathbf{29}$
* Output: $50 \rightarrow$ Input: $50 + 5 = \mathbf{55}$

Final Answer:
Section A Outputs:
(Add 5): 7, 9, 10, 16
(Add 8): 12, 20, 14, 13
(Add 15): 16, 19, 18, 30
(Subtract 1): 12, 3, 8, 22
(Subtract 8): 12, 5, 28, 76
(Subtract 20): 2, 136, 88, 33
(Multiply by 2): 8, 12, 20, 4
(Multiply by 5): 40, 55, 35, 45
(Divide by 2): 4, 20, 50, 12

Section B Missing Numbers:
(Add 4): Output 5, Input 8, Input 25, Output 50
(Add 7): Input 6, Output 20, Input 12, Output 28
(Add 12): Output 18, Input 18, Input 62, Input 86
(Subtract 1): Input 11, Input 18, Output 7, Input 100
(Subtract 3): Output 4, Input 4, Input 6, Output 348
(Subtract 5): Input 10, Input 18, Input 29, Input 55