Year 4 Number and place value Return to Primary Maths Resources

Teacher resources.

Gordons countdown

Student resources.

The forgotten code: a brain teaser

A man wanted to get into his work building, but he had forgotten his code. However, he did remember five clues. These are what those clues were:

  • The fifth number plus the third number equals fourteen.
  • The fourth number is one more than the second number.
  • The first number is one less than twice the second number.
  • The second number plus the third number equals ten.
  • The sum of all five numbers is 30.
  • What were the five numbers and in what order?

    1. I think of a number. I add 16 and my answer is 36. What was my number?
    2. I think of a number. I subtract 25 and add 2. My answer is 27, what was my number?
    3. I think of a number. I add 15 and then multiply by 2. My answer is 32, what was my number?