KS2 Primary Maths Age 9-13 - Number Problem: - Explained

The video tutorial explains a math problem where Helen starts with an unknown number, multiplies it by two, adds six, and divides the result by four to get 2.5. The instructor demonstrates how to reverse these operations to find the original number, which is 2. The process involves multiplying 2.5 by four, subtracting six, and dividing by two. The tutorial also discusses input and output machines, emphasizing the importance of reversing operations to solve such problems.

What is the first operation Helen performs on her number?

• Subtracts six

• Divides by four

• Adds six

• Multiplies by two

What is the final result after Helen performs all her operations?

• 4

• 2.5

• 6

• 10

What is the first step in reversing the operations to find the original number?

• Add six

• Multiply by four

• Divide by two

• Subtract six

After reversing the operations, what is the original number Helen started with?

• 4

• 6

• 2

• 10

What concept is used to describe the process of reversing operations to find the original input?

• Reverse engineering

• Output machines

• Input machines

• Input and output machines