Solution Found!
How many six-digit numbers are there? How many of them
Chapter , Problem 1(choose chapter or problem)
QUESTION:
How many six-digit numbers are there? How many of them contain the digit 5? Note that the first digit of an n-digit number is nonzero.
Questions & Answers
QUESTION:
How many six-digit numbers are there? How many of them contain the digit 5? Note that the first digit of an n-digit number is nonzero.
ANSWER:Step 1 of 4
Let us consider be sets with elements, then there are ways. We choose an element of first then an element of and lastly an element.
Here, let the set of all possible outcomes of the kth digit is
The first digit is non-zero then,
Since second to sixth digit may contains 0 then,