posted by lanz on .
HOW MANY SEVEN-DIGIT NUMBERS LESS THAN 1,048,000 CAN BE MADE USING THE DIGITS 0,1,4,6,7,8,AND 9? THINK: MAKE A LIST OF POSSIBLE WAYS TO REPRESENT YOUR SEVEN-DIGIT NUMBERS
since the number must be < 1 048 000
the number must be like
104ABCD where A can only be 6 or 7
so the ABCD part can be filled in
2x3x2x1 or 12 ways
I will leave it up to you to list those 12 numbers.
Go about it systematically