Malvern Save The Children Christmas Quiz
Quizzes & Puzzles0 min ago
Phil has a 2x2 grid and a bag of different coloured counters, he can put one counter in each of the four squares. He calculates that he can make 2401 different grids with his counters.
assuming he has at least four of each coloured counter, how many different grids could he make with one extra colour?
No best answer has yet been selected by skilliyay. Once a best answer has been selected, it will be shown here.
For more on marking an answer as the "Best Answer", please visit our FAQ.Suppose he has x different colours available. It is implicit in the question that he can repeat colours if he wishes.
That means he has x choices for each of the four squares. That is, he has a total of x times x times x times x choices. This x to the power 4.
2401 is 7 to the power 4. Therefore he started with 7 colours.
With 8 colours he could make 8 to the power 4 different grids.
8 to the power 4 is 4096