Question 1

LEVEL 1

Below is a function machine.

What is the output if the input is 4?

Select the correct answer from the list below:

A: 24

B: 18

C: 32

D: 4

 

CORRECT ANSWER: A: 24

WORKED SOLUTION:

First add 2: 4+2=6

Then multiply by 4: 6 \times 4 = 24

 

 

Question 2

LEVEL 1

Below is a function machine.

What is the input if the output is 3?

Select the correct answer from the list below:

A: 36

B: 18

C: 42

D: 24

 

CORRECT ANSWER: A: 36

WORKED SOLUTION:

We reverse the order or operations, and do the opposite operation.

The output is 3, so we first add 3: 3+3=6

We then multiply by 6: 6 \times 6 = 36

 

 

Question 3

LEVEL 1

Below is a function machine.

There is an operation missing. Which of the following operations does not work?

Select the correct answer from the list below:

A: \times 3

B: - 10

C: \div 3

D: \times \frac{1}{3}

 

CORRECT ANSWER: A: \times 3

WORKED SOLUTION:

11+4=15

15 \times 3 = 45, not 5

The other 3 operations give 5 as the output

 

 

Question 4:

LEVEL 1

Below is a function machine.

What is the output if the input is 7?

Select the correct answer from the list below:

A: 2.1

B: 15.5

C: 2.5

D: \frac{70}{3}

 

CORRECT ANSWER: A: 2.1

WORKED SOLUTION:

First multiply by 1.5: 7 \times 1.5 = 10.5

Then divide by 5: 10.5 \times 5 = 2.1

 

 

 

Question 5:

LEVEL 1

Below is a function machine.

What is the input if the output is 13?

Select the correct answer from the list below:

A: 22

B: 25

C: 4

D: 0

 

CORRECT ANSWER: A: 22

WORKED SOLUTION:

We reverse the order or operations, and do the opposite operation.

The output is 13, so we first multiply by 3: 13 \times 3 = 39

We then subtract 17: 39 - 17 = 22