In the end, the answer to the puzzle is simpler than it seems: the trick lies in multiplying the first number by 3. So, for the equation 5 = 15, you multiply 5 by 3 to get 15; for 7 = 21, you multiply ...
Solve this brain-busting BBC Bitesize challenge. Can you work out this shape puzzle in 90 seconds? Brainteaser of the week: Can you crack the code to open the safe? Put your code-breaking skills ...