How-many-numbers-from-1-to-999-do-n ot-have-any-repeated-digits? And how-many-are-even?

• The single-digit numbers 1-9 do not have any repeated digits, so they contribute 9 numbers.

• Of double-digit numbers 10-99, the first digit can be picked from 1-9 and the second from 0-9 minus whichever one is picked for the first digit, so they contribute 9×(10 - 1) = 81 numbers.

• Of the triple-digit numbers 100-999, the first digit is picked from 1-9 and the second and third digits from 0-9, so they contribute 9×(10 - 1)×(10 - 2) = 648 numbers.

So there are 9 + 81 + 648 = 738 numbers from 1-999 without repeated digits.

Of these numbers, the ones that are even end in 0, 2, 4, 6, or 8.

• Of the single-digits, there are 4 numbers.

• Of the double-digits, the first digit can be chosen from 1-9 and the second from {0, 2, 4, 6, 8}.

•• If the first digit is odd and picked from {1, 3, 5, 7, 9}, then they contribute 5×5 = 25 numbers.

•• If the first digit is even, then they contribute 4×(5 - 1) = 16 numbers (because the first digit can't be 0).

• Of the triple-digits, the third digit is picked from {0, 2, 4, 6, 8}.

•• If both the first and second digits are odd, then they contribute 5×(5 - 1)×5 = 100 numbers.

•• If the first is odd and the second is even, then they contribute 5×5×(5 - 1) = 100 numbers.

•• If the first is even and the second is odd, then they contribute 4×5×(5 - 1) = 80 numbers.

•• If both are even, then they contribute 4×(5 - 1)×(5 - 2) = 48 numbers.

So there are 4 + (25 + 16) + (100 + 100 + 80 + 48) = 373 even numbers from 1-999 with no repeating digits.

kk.bj.

step-by-step explanation:

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black/brown

step-by-step explanation:

well, you see here, jamal was born to 2 parents, his mother who he lives with and his father who left at a young age and who happens to be younger than him. he stole cookies because he has to steal food due to the fact that he spends his government poverty checks on pot and women.