1-step function machines.
Get ready to explore how function machines work with just one step between input and output. Can you spot the pattern and work out the missing numbers?

🙂 = Correct, ☹️ = Incorrect

📌 Rules

• Finding the output (Forward direction): Apply the operation directly to the input number. For example, if the input is 8 and the rule is + 5, calculate 8 + 5 = 13 to find the output.

• Finding the input (Reverse direction): Apply the inverse (opposite) operation to the output number. For example, if the output is 24 and the rule is × 3, do the inverse operation (24 ÷ 3 = 8) to work out the input.

💡 Tips

• Know your inverse pairs: Addition (+) pairs with subtraction (–), and multiplication (×) pairs with division (÷).

• Quick typing on our platform: Typing your answer is designed to be super quick and simple! Just type plain digits like 13 or 8 without adding any spaces, letters, or symbols.

⚠️ Warnings

• Do not use the forward rule when working backwards: If you are given the output and need to find the input, going forwards by mistake (e.g. calculating 24 × 3 = 72 instead of dividing) is a very common error.

• Check negative numbers: If an input is negative or a rule involves subtracting a larger number, count carefully across zero on a number line.