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Very hard maths GCSE question

Eddie needs to choose a six digit code for his computer password. How many codes can Eddie create using six numbers.

The answer is a million but I don't know why. Can anyone please explain?

Reply 1

archipelaglobule

The number of digits he can choose from when selecting any one of the numbers of his code is 10. (He can choose 0, 1, 2, 3, 4, 5, 6, 7, 8 or 9).
So he has six digits to choose, and there are 10 possibilities for each one.
The number of possible codes is therefore 10 x 10 x 10 x 10 x 10 x 10 = 10^6 (10 to the power of 6) = 1,000,000 = 1 million.

If it had been a two-digit code, it would have been 10 x 10 = 10^2 = 100, 10^3 for a three-digit code, 10^4 for a four-digit code, etc.

Hope that helps :smile: