8
Just multiply one pair of your numbers to give you a product, and then multiply their product by your third number.
You can make: 1 combination containing 0 digits, 7 combinations containing 1 digits, 21 combinations containing 2 digits, 35 combinations containing 3 digits, 35 combinations containing 4 digits, 21 combinations containing 5 digits, 7 combinations containing 6 digits, and 1 combinations containing 7 digits. That makes 2^7 = 128 in all.
It can have up to 5 digits.
-- Ignore the decimal point; just multiply the two whole numbers. -- After the multiplication is done, put the decimal point back into the product. Put it in the right place so that the product has as many digits after the point as the original decimal had. If there aren't enough digits in the product to do that, add some zeros to the left end of it.
It can have one . . . 1.0 x 1.0 = 1 It can have two . . . 1.0 x 0.1 = 0.1 It can have three . . . 10 x 10 = 100 It can have four . . . 99 x 99 = 9801 and .01 x .01 = .0001
1, 3 and 9
A number divisible by 123456789 must be 0 or bigger than 123456789. It must, therefore have 1 digit or 9 digits (or more). A remainder of 1 makes no difference to the number of digits. In any case, there can be no number of 4 digits that is divisible by 123456789.
Just multiply one pair of your numbers to give you a product, and then multiply their product by your third number.
123456789 X 1234567890 = 152415787501905210
222
5040 different 4 digit numbers can be formed with the digits 123456789. This is assuming that no digits are repeated with each combination.
There are 3024 of them.
You can make: 1 combination containing 0 digits, 7 combinations containing 1 digits, 21 combinations containing 2 digits, 35 combinations containing 3 digits, 35 combinations containing 4 digits, 21 combinations containing 5 digits, 7 combinations containing 6 digits, and 1 combinations containing 7 digits. That makes 2^7 = 128 in all.
It can have up to 5 digits.
A repeating sequence of numbers ! The digits 123456789 are simply repeated over and over.
There are 60480 numbers.
-123456787